Display device and electronic apparatus

ABSTRACT

The present display device includes a liquid crystal panel having a liquid crystal layer between an array substrate and a facing substrate. The array substrate has an electrode layer having an upper electrode and a lower electrode facing each other in a Z direction, and an opening including a plurality of slits extending in an X direction is formed in the upper electrode and the lower electrode. The liquid crystal layer is provided on the electrode layer, liquid crystal molecules in vicinity regions on one side and the other side of the opening which face each other in a width direction of each slit are oriented as rotating in reverse to each other, and the facing substrate has a conductive layer.

CROSS REFERENCES TO RELATED APPLICATIONS

The present application claims priority to Japanese Priority PatentApplication JP 2012-236500 filed in the Japan Patent Office on Oct. 26,2012, the entire content of which is hereby incorporated by reference.

BACKGROUND

The present invention relates to a technique for a display device and anelectronic apparatus. More particularly, the present invention relatesto a liquid crystal display device of a transverse electric field modeor others.

In liquid crystal display devices mounted on various electronicapparatuses or other, a transverse electric field mode and alongitudinal electric field mode are used as a mode for applying anelectric field to a liquid crystal layer. Also, as the transverseelectric field mode, IPS (In-Plane-Switching) mode, FFS (Fringe FieldSwitching) mode, or others is known. This transverse electric field modeis advantageous in a wider viewing angle and a higher aperture ratiothan those of the longitudinal electric field mode. In the presentspecification, note that the aperture ratio is assumed to be an arearatio of an effective region for display in one pixel region.

Japanese Patent Application Laid-Open Publication No. 2008-52161 (PatentDocument 1) discloses a technique regarding a liquid crystal displaydevice of the FFS mode. The Patent Document 1 describes a technique forthe liquid crystal display device of the FFS mode capable of increasingthe aperture ratio without complicating a structure of the liquidcrystal display device so as to achieve bright display.

SUMMARY

However, the liquid crystal display device of the transverse electricfield mode such as the FFS mode described above has such a problem as alow response speed. The response speed described here is a speed atwhich, when a voltage is applied between an upper electrode and a lowerelectrode included in a certain pixel, a transmittance of liquid crystalin the pixel transits from a certain value to a different value.Specifically, the response speed is defined by time required fortransition from, for example, an OFF state with transmittance of 0 to,for example, an ON state with transmittance of 1, or by time requiredfor reverse transition of that.

In consideration of the above-described points, a main preferred aim ofthe present invention is to provide a display device or others capableof increasing the response speed so as to improve display quality andothers more than that of a liquid crystal display device of aconventional transverse electric field mode such as the FFS mode orothers in addition to widening the viewing angle and increasing theaperture ratio. More particularly, a main preferred aim of the presentinvention is to provide a display device or others capable of enhancingorientation stability of liquid crystal of a liquid crystal layer so asto improve the transmittance.

A typical aspect of the present inventions is a display device and anelectronic apparatus with a feature having the following structure.

(1) A display device of the aspect includes: an electrode layer beingprovided on a first substrate and including a first electrode and asecond electrode, the second electrode facing the first electrode andhaving an opening including a plurality of slits whose extendingdirections are the same as each other; a liquid crystal layer beingprovided between the first substrate and a second substrate facing thefirst substrate and having liquid crystal molecules oriented as rotatingin reverse to each other in vicinity regions on one side and the otherside of the opening which face each other in a width direction; and aconductive layer being provided on the second substrate.

Also, when orientation of liquid crystal of the liquid crystal layer iscontrolled, the conductive layer has the same potential as a potentialof the first electrode or the second electrode.

(2) More particularly, the display device further includes: a firstorientation film being provided between the first substrate and theliquid crystal layer and being subjected to an orientation process in afirst orientation direction which is a substantially parallel directionor substantially orthogonal direction of the extending direction of theslits; and a second orientation film being provided between the secondsubstrate and the liquid crystal layer and being subjected to anorientation process in a second orientation direction which is aparallel direction of the first orientation direction of the firstorientation film. And, in an initial orientation state of the liquidcrystal layer, long axes of the liquid crystal molecules are aligned inthe first orientation direction. In the application of the voltage tothe first electrode and the second electrode, the long axes of theliquid crystal molecules are oriented as rotating in an in-planedirection of the substrate so that the liquid crystal molecules rotateclockwise in a vicinity region including one side of both sides of anelectrode forming the slits and the liquid crystal molecules rotatecounterclockwise in a vicinity region including the other side thereof.

(3) More particularly, the second electrode is a pixel electrode, thefirst electrode is a common electrode, and the first electrode and theconductive layer have the same potential as each other when theorientation of the liquid crystal of the liquid crystal layer iscontrolled.

(4) More particularly, the second electrode is a common electrode, thefirst electrode is a pixel electrode, and the second electrode and theconductive layer have the same potential as each other when theorientation of the liquid crystal of the liquid crystal layer iscontrolled.

(5) For example, the conductive layer is a light-shielding film.Alternatively, the conductive layer is an electrostatic protectivelayer. Alternatively, the conductive layer is a transparent electrode.

(6) More particularly, in the display device, the second substrate has atransmission-side electrode and a reception-side electrode which areelectrodes for configuring a touch sensor function as the conductivelayer, and the first electrode or the second electrode and thetransmission-side electrode or the reception-side electrode have thesame potential as each other when the orientation of the liquid crystalof the liquid crystal layer is controlled.

(7) More particularly, in the display device, the second substrate hasone electrode of a transmission-side electrode and a reception-sideelectrode which are electrodes for configuring a touch sensor functionas the conductive layer, the first substrate has the other electrode ofthe transmission-side electrode and the reception-side electrode, andthe first electrode or the second electrode and the one electrode of thetransmission-side electrode and the reception-side electrode have thesame potential as each other when the orientation of the liquid crystalof the liquid crystal layer is controlled.

(8) More particularly, the display device further includes a firstdriver connected to a first electrode line for configuring a pixel, asecond driver connected to a second electrode line for configuring apixel, a third driver connected to the second electrode and the firstelectrode, and a controller for controlling the first to third drivers.

(9) More particularly, the display device includes the first to thirddrivers, a fourth driver connected to the transmission-side electrodeand the reception-side electrode, and a controller for controlling thefirst to fourth drivers.

(10) More particularly, the electronic apparatus includes a control unitfor performing a display control process to the display device and astorage unit for storing display data to be provided to the displaydevice.

According to a typical aspect of the present inventions, the responsespeed can be increased so as to improve display quality and others morethan that of a liquid crystal display device of a conventionaltransverse electric field mode such as the FFS mode or others inaddition to widening the viewing angle and increasing the apertureratio. That is, according to the typical aspect of the presentinventions, a liquid crystal display device of a high-speed transverseelectric field mode or others can be provided. In other words, accordingto the typical aspect of the present inventions, the response speed inpixel display can be increased so as to improve brightness, that is, thetransmittance or the orientation stability of the liquid crystal orothers, so that display quality and others can be improved.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram illustrating a block structure of a display deviceand an electronic apparatus of a first embodiment;

FIG. 2 is a diagram illustrating a schematic structure of across-sectional surface of a liquid crystal panel of the display deviceof the first embodiment;

FIG. 3 is a diagram illustrating a schematic structure of across-sectional surface of a liquid crystal panel of a display device ofa first modification example of the first embodiment;

FIG. 4 is a diagram illustrating a schematic structure of across-sectional surface of a liquid crystal panel of a display device ofa second modification example of the first embodiment;

FIG. 5 is a diagram illustrating a schematic structure of across-sectional surface of a liquid crystal panel of a display device ofa third modification example of the first embodiment;

FIG. 6 is a diagram illustrating a first mounting structure example ofthe display device of the first embodiment;

FIG. 7 is a diagram illustrating a second mounting structure example ofthe display device of the first embodiment;

FIG. 8 is a diagram collectively illustrating structure examples of anupper electrode and a lower electrode of the first embodiment or others;

FIG. 9 is diagrams illustrating structure examples (a) and (b) of anupper electrode and an opening in a case of a structure A;

FIG. 10 is diagrams illustrating structure examples (a) and (b) of anupper electrode and an opening in a case of a structure B;

FIG. 11A is a diagram illustrating a plan structure example of pixels ina case of the structure A and a structure α;

FIG. 11B is a diagram illustrating a plan structure example of pixels ina case of the structure A and a structure β;

FIG. 11C is a diagram illustrating a plan structure example of pixels ina case of the structure B and the structure α;

FIG. 11D is a diagram illustrating a plan structure example of pixels ina case of the structure B and the structure β;

FIG. 12 is a diagram illustrating a layout pattern of overlap or othersamong the upper electrode, the lower electrode, and a conductive layerin X, Y, and Z spaces;

FIG. 13 is a diagram illustrating a plan structure example of pixels inthe first embodiment;

FIG. 14 is partially-enlarged diagrams of FIG. 13 for describing liquidcrystal orientation or others, in which an item (a) illustrates a caseof voltage OFF and an item (b) illustrates a case of voltage ON;

FIG. 15 is diagrams on a cross-sectional surface A1-A2 of FIG. 13 fordescribing the liquid crystal orientation or others, in which an item(a) illustrates the case of voltage OFF and an item (b) illustrates thecase of voltage ON;

FIG. 16 is diagrams for describing a principle of a capacitive touchsensor of a mutual capacitance type;

FIG. 17 is a diagram illustrating a block structure of a display deviceand an electronic apparatus of a second embodiment;

FIG. 18 is a diagram illustrating a first structure example of a touchsensor of the second embodiment or others;

FIG. 19 is a diagram illustrating a second structure example of thetouch sensor of the second embodiment or others;

FIG. 20 is a diagram illustrating a schematic structure of across-sectional surface of a liquid crystal touch panel of a liquidcrystal display device equipped with a touch sensor, which is a displaydevice of the second embodiment;

FIG. 21 is a diagram illustrating a schematic structure of across-sectional surface of a liquid crystal touch panel of a liquidcrystal display device equipped with a touch sensor, which is a displaydevice of a first modification example of the second embodiment; and

FIG. 22 is a diagram illustrating an example of drive control from adriver side in the second embodiment or others.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention are described indetail based on the drawings. Note that in all drawings for describingthe embodiments, the same portions are denoted by the same referencesymbol in principle, and repetitive description thereof is omitted.Also, in the drawings, in order to easily understand features,cross-sectional hatching is appropriately omitted, and principalcomponents are emphatically illustrated, and a dimensional ratio orothers may differ from an actual ratio. For description, two directionsorthogonal to each other in an in-plane direction of a substratecorresponding to a screen are assumed to be “X” and “Y” directions, anda direction perpendicular to the substrate surface, that is, a directionperpendicular to both of the X and Y directions, is assumed to be a “Z”direction.

<First Embodiment>

A first embodiment describes a case that a technique found by thepresent inventor of the present application is applied to a liquidcrystal display device by which color moving images can be displayed ona screen and is applied to an electronic apparatus having the liquidcrystal display device mounted thereon.

[Electronic Apparatus and Liquid Crystal Display Device]

FIG. 1 illustrates a block structure of a liquid crystal display device100 which is a display device of the first embodiment, and an electronicapparatus 200 having the liquid crystal display device 100 mountedthereon. The electronic apparatus 200 includes: the liquid crystaldisplay device 100; a control unit 201; a storage unit 202; an inputunit 203; an output unit 204; a display interface unit 205; and others.A display I/F unit in FIG. 1 is the abbreviated expression of a displayinterface unit.

The control unit 201 is configured of, for example, a CPU (CentralProcessing Unit), a ROM (Read Only Memory), a RAM (Random AccessMemory), programs that operate thereon, and others. For example, the CPUperforms a control process on the electronic apparatus 200 such as adisplay control process with a computation process in accordance with aprogram loaded from the ROM to the RAM. The storage unit 202 isconfigured of a primary memory, a secondary memory, and data informationsuch as video data stored therein. In other words, the storage unit 202stores display data to be provided to the liquid crystal display device100. The input unit 203 is configured of an input device such as abutton and its interface processing unit. The output unit 204 isconfigured of an output device except for a display device and itsinterface processing unit. The display interface unit 205 is connectedto the liquid crystal display device 100, and performs its interfaceprocess. The electronic apparatus 200 has other components notillustrated, such as a communication interface unit and a power supplyunit.

The liquid crystal display device 100 has a liquid crystal panel 1 andan LCD (Liquid Crystal Display) driver 101 serving as a controller formain drive control. Also, the liquid crystal display device 100 also hasa gate driver 111, a data driver 112, and an upper/lower-electrodedriver 113 serving as drivers which are drive circuits for eachelectrode line of the liquid crystal panel 1. Each driver of the gatedriver 111, the data driver 112, and the upper/lower-electrode driver113 is achieved by, for example, mounting with a flexible printedcircuit board connected to the liquid crystal panel 1 and equipped withan IC chip thereon, that is, by COP (Chip On Film), or by mounting witha circuit formed on a glass substrate in a frame part of the liquidcrystal panel 1, that is, by COG (Chip On Glass). Note that the driversmay be appropriately integrated with or separated from each other. Whilethe liquid crystal panel 1 and each driver are separated from each otherin the drawing, the driver may be mounted in the liquid crystal panel 1.

To the control unit 201 of the electronic apparatus 200, for example, avideo signal is inputted from outside of the control unit 201.Alternatively, inside the control unit 201, a video signal is generated.The video signal and a control signal serving as control instructioninformation are provided from the control unit 201 via the displayinterface unit 205 to the LCD driver 101. The LCD driver 101 providesthe video signal and a control signal such as a timing signal to eachdriver of the gate driver 111, the data driver 112, and theupper/lower-electrode driver 113 for controlling them. The gate driver111 follows the control of the LCD driver 101 to provide a scanningsignal to a group of gate lines 41 of the liquid crystal panel 1. Thedata driver 112 follows the control of the LCD driver 101 to provide adata signal in accordance with a pixel value to the group of the datalines 42 of the liquid crystal panel 1. The upper/lower-electrode driver113 follows the control of the LCD driver 101 to provide correspondingvoltage signals to an upper electrode 31 and a lower electrode 32 (seeFIG. 2 described later) of the liquid crystal panel 1, that is, a pixelvoltage to a pixel electrode PIX (see FIG. 2 described later) and acommon voltage to a common electrode COM (see FIG. 2 described later).In this manner, a transmittance per pixel is controlled.

As examples of the electronic apparatus 200, various electronicapparatuses are cited, such as a television device, that is, a liquidcrystal television device, a personal-computer display, a digitalcamera, a video camera recorder (camcorder), a laptop personal computer,a mobile phone such as a smartphone, a mobile terminal such as a tabletcomputer, a display for a car navigation system, and others. When theelectronic apparatus 200 is, for example, the liquid crystal televisiondevice or the personal-computer display, a filter glass or others isadded to a front surface of the liquid crystal display device 100, andthe liquid crystal display device 100, the filter glass, and others areheld by a casing. When the electronic apparatus 200 is, for example, thedigital camera or the video camera recorder, a display unit such as acamera finder is configured of the liquid crystal display device 100.When the electronic apparatus 200 is, for example, the laptop personalcomputer, a screen unit is configured of the liquid crystal displaydevice 100. When the electronic apparatus 200 is, for example, themobile phone, a screen unit is configured of the liquid crystal displaydevice 100.

[Liquid Crystal Panel of First Embodiment]

FIG. 2 illustrates a schematic structure on a Y-Z cross-sectionalsurface of the liquid crystal panel 1 of the display device of the firstembodiment. Note that the liquid crystal panel 1 of the first embodimentis particularly referred to as a liquid crystal panel 1A. In the liquidcrystal panel 1A of the first embodiment, the lower electrode 32 servingas the common electrode COM on the glass substrate 11 on an arraysubstrate 10 side and a conductive layer 60 on the glass substrate 21 ona facing substrate 20 side have the same potential as each other. Thatis, in the image displaying, that is, in the control of the liquidcrystal orientation of the pixel in the liquid crystal panel 1A of thefirst embodiment, the same voltage V0 is applied from a not-illustrateddriver side connected to the liquid crystal panel 1A to the lowerelectrode 32 and the conductive layer 60 which are two types of layersarranged at different positions from each other in the Z direction. Inother words, a potential of the conductive layer 60 is equal to apotential of the lower electrode 32 in the control of the liquid crystalorientation of the liquid crystal layer. In this manner, in viewing fromthe Z direction, that is, in an X-Y planar view, such an effect that theorientation stability of the liquid crystal is increased can be obtainedin regions including a vicinity of the conductive layer 60 (see FIG. 21described later). In other words, in the X-Y planar view, such an effectthat the orientation of the liquid crystal is stabilized can be obtainedin the region where the conductive layer 60 is formed and the region inthe vicinity of the conductive layer 60. That is, in the imagedisplaying, such an effect that responsiveness is favorable so as toincrease the display quality can be obtained.

In the first embodiment, the upper electrode 31 is the pixel electrodePIX, and the lower electrode 32 is the common electrode COM (see astructure A of FIG. 8 described later). Also, a shape of an opening 50can be various any shapes, and the shape of the opening 50 can be, forexample, an alternate both-side comb teeth shape (see a structure α ofFIG. 8 described later). The position of the conductive layer 60 in theZ direction and the X-Y planar shape can be any, and can be a positionand a shape in accordance with the function of the conductive layer 60.

The display device includes the liquid crystal panel 1A, and the liquidcrystal panel 1A has an array substrate 10 serving as a first substrate,a facing substrate 20 serving as a second substrate, and a liquidcrystal layer 30 interposed and sealed therebetween. Note that FIG. 2illustrates a schematic structure, and illustrations of an insulatingfilm, an orientation film, a polarizing plate, a backlight, and otherpublicly-known components are omitted. A reference symbol “PA”represents a display area. A reference symbol “V0” represents a voltageapplied to the lower electrode 32 and the conductive layer 60 arrangedat different positions from each other in the Z direction.

The array substrate 10 is a substrate structure body including astructure on a back surface side with respect to a line of sight and theglass substrate 11. In other words, the array substrate 10 is asubstrate structure body including the glass substrate 11 and having astructure on the back surface side. The lower electrode 32, a dielectricfilm 33, and the upper electrode 31 are stacked on one side with respectto the glass substrate 11 in the Z direction, that is, on the glasssubstrate 11. While a gate line, a TFT unit, and others are provided onthe glass substrate 11, they will be described in detail later. Theupper electrode 31 and the lower electrode 32 are formed to be layeredso as to face in parallel to each other via the dielectric film 33. Anelectrode layer including the upper electrode 31 and the lower electrode32 has a portion where the upper electrode 31 and the lower electrode 32overlap each other when viewed in the Z direction and a portion wherethe upper electrode 31 and the lower electrode 32 do not overlap eachother when viewed in the Z direction. By this shape in the X-Y planarview, the opening 50 including a slit S (see FIG. 8 described later) isformed. On the electrode layer including the upper electrode 31 and thelower electrode 32 with the opening 50 formed thereon, a fringe electricfield occurs for controlling the liquid crystal orientation of theliquid crystal layer 30 in X and Y directions which are in-planedirections of the substrate. In other words, the fringe electric fieldoccurs for controlling the liquid crystal orientation of the liquidcrystal layer 30 in vicinity of the opening 50. Therefore, the liquidcrystal panel 1A is the liquid crystal display device of the transverseelectric field mode.

In the first embodiment, in the upper electrode 31 and the lowerelectrode 32, the upper electrode 31 is the pixel electrode PIX, and thelower electrode 32 is the common electrode COM. On the electrode layerincluding the upper electrode 31 and the lower electrode 32, the opening50 having the slit S extending in a transverse direction, that is, inthe X direction, corresponding to the high-speed transverse electricfield mode is formed as illustrated in FIG. 11A described later orothers. A structure example of the upper electrode 31 and the lowerelectrode 32 can be various structure examples summarized in FIG. 8described later.

The facing substrate 20 is a substrate structure body including astructure on a front surface side and the glass substrate 21. In otherwords, the facing substrate 20 is a substrate structure body includingthe glass substrate 21 and having a structure on the front surface sidewith respect to the line of sight. In the facing substrate 20, theconductive layer 60 is provided at any position in the Z direction suchas an inner surface side or an outer surface side on the glass substrate21. Note that the inner surface side indicates one of both sides of theglass substrate 21 in the Z direction which is close to the liquidcrystal layer 30, and the outer surface side indicates the other of bothsides of the glass substrate 21 in the Z direction which is away fromthe liquid crystal layer 30. FIG. 2 illustrates a case in which theconductive layer 60 is provided on the inner surface side. Theconductive layer 60 is a layer of a conductive electrode or others. Aposition of the conductive layer 60 in the facing substrate 20 in the Zdirection is not particularly limited. Also, a distance between thelower electrode 32 and the conductive layer 60 in the Z direction is notparticularly limited, either. Further, the shape and the position of theconductive layer 60 in the facing substrate 20 in the X and Y directionsare not particularly limited.

The lower electrode 32 serving as the common electrode COM is formed asa solid layer over a region including a plurality of pixels such as theentire screen. Also, the lower electrode 32 is controlled by applicationof a common voltage thereto so as to have the same potential regardlessof the pixel. Note that the lower electrode 32 may not be formed as thesolid layer over the entire screen, and a plurality of lower electrodes32 may be formed so as to be arranged for the plurality of respectivepixels. In such a case that the plurality of lower electrodes 32 areformed, the plurality of lower electrodes 32 are connected to each othervia a common electrode line. The upper electrode 31 serving as the pixelelectrode PIX is formed for each pixel. A shape of the upper electrode31 is a rectangular shape. Also, the upper electrode 31 is controlled soas to have a different potential for each pixel. The upper electrode 31and the lower electrode 32 are transparent electrodes each made of amaterial having conductivity and transmission property with respect tovisible light, such as ITO (Indium-Tin-Oxide).

The liquid crystal of the liquid crystal layer 30 is sealed between thearray substrate 10 and the facing substrate 20 via first and secondorientation films serving as orientation films. The array substrate 10and the facing substrate 20 are connected to each other by a sealingmaterial in the frame part of the liquid crystal panel 1 or others, sothat the liquid crystal is sealed between the array substrate 10 and thefacing substrate 20. The first orientation film is provided between theliquid crystal layer 30 and the electrode layer including the upperelectrode 31 and the lower electrode 32 on the array substrate 10 side,and the second orientation film is provided between the liquid crystallayer 30 and the facing substrate 20. An orientation process for theliquid crystal by antiparallel orientation which supports the structureof the opening including the slit S, more particularly, a rubbingprocess is performed for the first and second orientation films, so thatan orientation state of the liquid crystal of the liquid crystal layer30 obtained when no potential difference is provided between the upperelectrode 31 and the lower electrode 32, that is, an initial orientationstate thereof becomes a predetermined orientation state, and thehigh-speed transverse electric field mode which is the present method ofdriving the liquid crystal is achieved.

In the image displaying, a predetermined potential difference inaccordance with modulation of the pixel transmittance is providedbetween the upper electrode 31 and the lower electrode 32 via thedielectric film 33 by applying a voltage from the driver side to theupper electrode 31 and the lower electrode 32. By the potentialdifference, the fringe electric field is caused in the vicinity of theopening 50. By the caused fringe electric field, the liquid crystalorientation is controlled so that the liquid crystal molecules rotatemainly in the X and Y directions which are the in-plane directions ofthe substrate. In other words, by the fringe electric field, the liquidcrystal orientation is controlled so that the liquid crystal moleculesrotate in a substrate plane.

A lower polarizing plate and an upper polarizing plate are arranged on aback surface side of the array substrate 10, that is, a lower sidethereof, and on a front surface side of the facing substrate 20, thatis, an upper side thereof, respectively, so that a polarization state oftransmitted light is controlled by the lower polarizing plate and theupper polarizing plate. A transmission axis of the upper polarizingplate and a transmission axis of the lower polarizing plate areorthogonal to each other, and one of the transmission axes of the lowerpolarizing plate and the upper polarizing plate is in parallel to adirection of the liquid crystal orientation. The backlight or others isarranged on the back surface side of the array substrate 10, and anillumination state of the backlight or others is controlled by anot-illustrated driver for backlight control in accordance with thecontrol of the state of the liquid crystal orientation. The transmissionand polarization are controlled in the liquid crystal panel 1 inaccordance with the pixel state based on light emitted from thebacklight, so that an image is formed on the screen on the front surfaceside. In other words, the transmittance of the light emitted from thebacklight and the polarization state of transmitted light are controlledin each pixel, so that the image is displayed on the screen.

As described above, the same potential is provided for the lowerelectrode 32 and the conductive layer 60 arranged at different positionsfrom each other in the Z direction, so that the state of the liquidcrystal orientation in a space between these layers can be stabilized.In the first embodiment, the lower electrode 32 is used as the commonelectrode COM, the lower electrode 32 and the conductive layer 60 arecontrolled so as to have the same potential. In this manner, the effectof the orientation stability of the liquid crystal can be higher than,for example, that of a later-described first modification example of thefirst embodiment in which the upper electrode 31 is used as the commonelectrode COM.

When the lower electrode 32 and the conductive layer 60 are controlledso as to have the same potential, note that the same potential is notnecessarily maintained for the entire period of time. By maintaining thesame potential for a certain period of time or longer with respect tothe entire period of time, a proper effect can be obtained. Also, whenthe lower electrode 32 and the conductive layer 60 are controlled so asto have the same potential, exactly the same potential such as thevoltage V0 is not necessarily maintained. By maintaining the potentialin a range of a close potential to some extent, a proper effect can beobtained.

[Liquid Crystal Panel of First Modification Example of First Embodiment]

FIG. 3 illustrates a schematic structure of a Y-Z cross-sectionalsurface of the liquid crystal panel 1 of the display device of the firstmodification example of the first embodiment. Note that the liquidcrystal panel 1 of the first modification example of the firstembodiment is particularly referred to as a liquid crystal panel 1B. Inthe liquid crystal panel 1B of the first modification example of thefirst embodiment, the upper electrode 31 serving as the common electrodeCOM on the glass substrate 11 on the array substrate 10 side and theconductive layer 60 on the glass substrate 21 on the facing substrate 20side have the same potential. In the first modification example of thefirst embodiment, the upper electrode 31 is the common electrode COM,and the lower electrode 32 is the pixel electrode PIX (see a structure Bof FIG. 8 described later). Also, a shape of an opening 50 can bevarious any shapes, and can be, for example, a one-side comb teeth shape(see a structure β of FIG. 8 described later).

Also in the first modification example of the first embodiment, theeffect that the orientation stability of the liquid crystal is increasedas similar to the first embodiment can be obtained in regions includingvicinity of the conductive layer 60 in the X-Y planar view. In otherwords, in the X-Y planar view, the effect that the orientation of theliquid crystal is stabilized can be obtained in the region where theconductive layer 60 is formed and the region in the vicinity of theconductive layer 60. In comparison between the first embodiment and thefirst modification example of the first embodiment, note that the effectof the orientation stability is higher in the first embodiment asdescribed above when two layers are controlled so as to have the samepotential as each other.

As similar to the first embodiment, note that an aspect in which thelower electrode 32 is the common electrode COM and one of the two typesof layers having the same potential is the lower electrode 32 will bedescribed below. However, as similar to the first modification exampleof the first embodiment, an aspect in which the upper electrode 31 isthe common electrode COM and one of the two types of layers having thesame potential is the upper electrode 31 is also possible.

[Liquid Crystal Panel of Second Modification Example of FirstEmbodiment]

FIG. 4 illustrates a schematic structure of a Y-Z cross-sectionalsurface of the liquid crystal panel 1 of the display device of thesecond modification example of the first embodiment. Note that theliquid crystal panel 1 of the second modification example of the firstembodiment is particularly referred to as a liquid crystal panel 1C. Inthe liquid crystal panel 1C of the second modification example of thefirst embodiment, the conductive layer 60 in the liquid crystal panel 1Aof the first embodiment is a light-shielding film 22. And, in the liquidcrystal panel 1C of the second modification example of the firstembodiment, the lower electrode 32 serving as the common electrode COMon the array substrate 10 and the light-shielding film 22 on the facingsubstrate 20 side have the same potential.

In the facing substrate 20, layers of the light-shielding film 22 and acolor filter 23 are provided. While a position of the light-shieldingfilm 22 in the facing substrate 20 in the Z direction is any position,the light-shielding film 22 is formed on an inner surface side on theglass substrate 21 in the structure example of FIG. 4. The color filter23 is arranged in accordance with pixel arrangement (see FIG. 11Adescribed later).

The light-shielding film 22 is made of a material having light shieldingproperty, that is, a light absorption property or low lighttransmittance property, such as a metal of Cr or others or alow-resistant resin containing carbon. Note that the light-shieldingfilm is also referred to as a black film. A main role of thelight-shielding film 22 is light shielding for reducing crosstalkbetween the pixels. When the light-shielding film 22 is made of theabove-described material such as Cr, the light-shielding film becomes alayer having conductivity, and corresponds to the conductive layer 60.The light-shielding film 22 is formed in, for example, a lattice shapewhich sections the pixels in accordance with the pixel arrangement (seeFIG. 11A described later).

In the facing substrate 20, the layers such as the light-shielding film22 and the color filter 23 are formed on the glass substrate 21. Here,the term “on the glass substrate 21” means a lower side as one side ofthe glass substrate 21 in the Z direction, which is a side close to theliquid crystal layer 30. The facing substrate 20 is also referred to asa CF substrate. Note that the light-shielding film 22 and the colorfilter 23 are arranged in the same layer as each other in the exampleillustrated in FIG. 4. However, they may be arranged in different layersfrom each other. Also, an overcoat layer or others having a function asa planarizing layer and a protective layer not illustrated may beprovided on the inner surface side which is the side close to the liquidcrystal layer 30 on the light-shielding film 22 and the color filter 23.Further, an electrostatic protective layer or others in addition to thepolarizing plate may be provided on the front surface side of the facingsubstrate 20.

According to the second modification example of the first embodiment,the effects or others as similar to the first embodiment are obtained,in which the orientation of the liquid crystal in the space between thelower electrode 32 and the light-shielding film 22 is stabilized so thatthe transmittance is improved by the orientation stability of the liquidcrystal in the region including the vicinity of the light-shielding film22 in the X-Y planar view. In other words, the effects or others areobtained, in which the orientation of the liquid crystal is stabilizedso that the transmittance is improved in the region where thelight-shielding film 22 is formed and the region in the vicinity of thelight-shielding film 22 in the X-Y planar view.

[Liquid Crystal Panel of Third Modification Example of First Embodiment]

FIG. 5 illustrates a schematic structure of a Y-Z cross-sectionalsurface of the liquid crystal panel 1 of the display device of the thirdmodification example of the first embodiment. Note that the liquidcrystal panel 1 of the third modification example of the firstembodiment is particularly referred to as a liquid crystal panel 1D. Inthe liquid crystal panel 1D of the third modification example of thefirst embodiment, the conductive layer 60 in the liquid crystal panel 1Aof the first embodiment is an electrostatic protective film 25. Theelectrostatic protective film 25 is also referred to as an electrostaticpreventing film. And, in the liquid crystal panel 1D of the thirdmodification example of the first embodiment, the lower electrode 32serving as the common electrode COM on the array substrate 10 and theelectrostatic protective film 25 on the facing substrate 20 side havethe same potential as each other.

The electrostatic protective layer 25 is provided at any position on thefacing substrate 20 in the Z direction. More particularly in the exampleillustrated in FIG. 5, the electrostatic protective layer 25 is providedat a position on the front surface side of the facing substrate 20, thatis, on the outer surface side of the glass substrate 21. Theelectrostatic protective layer 25 is a layer having a function whichprevents charging of static electricity on the screen of the liquidcrystal panel, in other words, a function which discharges the chargedstatic electricity to the outside of the liquid crystal panel, andcorresponds to the conductive layer 60 described by using FIG. 2. Notethat the example illustrated in FIG. 5 is an example in which adedicated layer to the function of the electrostatic protection isprovided, and is different from a later-described example in which atransmission-side electrode and a reception-side electrode are provided.

According to the third modification example of the first embodiment, theeffects or others as similar to the first embodiment are obtained, inwhich the orientation of the liquid crystal in the space between thelower electrode 32 and the electrostatic protective layer 25 isstabilized so that the transmittance is improved by the orientationstability of the liquid crystal in the region including the vicinity ofthe electrostatic protective layer 25 in the X-Y planar view. In otherwords, the effects or others are obtained, in which the orientation ofthe liquid crystal is stabilized so that the transmittance is improvedin the region where the electrostatic protective layer 25 is formed andthe region in the vicinity of the electrostatic protective layer 25 inthe X-Y planar view.

Note that the facing substrate 20 may be further provided with both ofthe layers such as the light-shielding film 22 and the color filter 23of the second modification example of the first embodiment and theelectrostatic protective layer 25 of the third modification example ofthe first embodiment. In this case, one of the light-shielding film 22and the electrostatic protective layer 25 may be controlled so as tohave the same potential as that of the other layer, or both of thelight-shielding film 22 and the electrostatic protective layer 25 may becontrolled so as to have the same potential as each other.

[Manufacturing Method]

A method of manufacturing the liquid crystal panel 1 includes, forexample, the following processes. Note that the second modificationexample of the first embodiment, that is, the case of the structure Awill be described below.

In a manufacturing process of the array substrate 10, layers of a gateline, a data line, a TFT part, and others are formed on one side of theglass substrate 11 in the Z direction, that is, on the glass substrate11. Then, an insulating film having a function serving as a planarizinglayer is formed thereon. The insulating film is made of a material suchas polyimide or silicon oxide. On the insulating film, a layer of thelower electrode 32 serving as the common electrode COM made of ITO isformed as, for example, a solid layer over the entire surface of theinsulating film. On the lower electrode 32 serving as the commonelectrode COM, the dielectric film 33 is formed as the solid layer overthe entire surface. The dielectric film 33 is formed as a planarizinglayer. The dielectric film 33 has insulating and protecting properties,is made of, for example, a material such as silicon nitride or siliconoxide, and is formed by a plasma CVD method or others. On a planesurface of the dielectric film 33, the layer of the upper electrode 31serving as the pixel electrode PIX made of ITO is formed as a patternlayer having an opening by photo-etching (photolithography etching) orothers. A thickness of the lower electrode 32 is, for example, 10 to 100nm, a thickness of the upper electrode 31 is, for example, 50 to 150 nm,and a thickness of the dielectric film 33 is, for example, 10 to 100 nm.On the upper electrode 31 serving as the pixel electrode PIX, the firstorientation film to which the orientation process is performed in afirst rubbing direction is formed. The first orientation film is formedby performing the orientation process such as a rubbing process to ahigh polymer material such as polyimide. Note that the orientationprocess is not limited to the rubbing process, and orientation processesof other methods such as an optical orientation process is alsoapplicable.

In the manufacturing process on the facing substrate 20 side, the layersof the color filter 23 and the light-shielding film 22 are formed on theglass substrate 21, and the overcoat layer or others having thefunctions serving as the planarizing layer and the protective layer isformed thereon. Here, the term “on the glass substrate 21” means a lowerside as one side of the glass substrate 21 in the Z direction. Thesecond orientation film to which the orientation process is performed ina second rubbing direction is formed thereon.

The liquid crystal layer 30 is formed by facing the array substrate 10and the facing substrate 20 each other, injecting liquid crystal betweenthe array substrate 10 and the facing substrate 20, and sealing theframe part with a sealer. A polarizing plate, a backlight, and othersare mounted on the back surface side of the liquid crystal panel 1, anda polarizing plate and others are mounted on the front surface side ofthe liquid crystal panel 1. To an electric end of the frame part of theliquid crystal panel 1, for example, a wiring for each driver isconnected. The liquid crystal panel 1 is manufactured as describedabove.

[Mount Structure Example (1)]

FIG. 6 illustrates a first mount structure example of the display deviceof the first embodiment including the liquid crystal panel 1, its drivercircuit, and others described above. The first mount structure examplecorresponds to a case in which the conductive layer 60 is provided onthe outer surface side of the facing substrate 20 in the firstembodiment and the first and third modification examples of the firstembodiment. In the first mount structure example, one end of an ITO pad93 serving as the lower electrode 32 on the glass substrate 11 on thearray substrate 10 side and one end of an ITO 91 serving as theconductive layer 60 on the glass substrate 21 on the facing substrate 20side are connected to each other by a conductive paste 92 serving as aconductive material in an end region of the liquid crystal panel 1 inthe X or Y direction.

The ITO pad 93 is formed at the end of the glass substrate 11 on theback surface side having an area wider than that of the glass substrate21 on the front surface side. The lower electrode 32 serving as thecommon electrode COM not illustrated is connected to the ITO pad 93. Tothe ITO pad 93, a driver not illustrated is connected. Also, as theconductive layer 60 on the facing substrate 20 side, the ITO 91 isformed on the outer surface side of the glass substrate 21. A referencesymbol 1101 denoted on an upper side of the ITO 91 denotes a polarizingplate provided on the front surface side of the facing substrate 20.Illustration of other components such as the liquid crystal layer 30 isomitted. The conductive paste 92 is formed so as to be connected to oneend of the ITO 91 being exposed and extending to an end region of theglass substrate 21 on the upper side and to one end of the ITO pad 93being exposed and extending to an end region of the glass substrate 11on the lower side. In this manner, the ITO 91 and the ITO pad 93 areconducted to each other.

According to the present mount structure, by, for example, applying thevoltage V0 from the driver side to the ITO pad 93, the same voltage V0can be applied from the ITO pad 93 to the lower electrode 32 and to theITO 91 serving as the conductive layer 60. In other words, in a pixelwriting period in the pixel display, for example, the voltage V0 can beapplied from the upper/lower-electrode driver 113 (see FIG. 1) to thelower electrode 32, and the voltage V0 can be applied from theupper/lower-electrode driver 113 to the conductive layer 60.

[Mount Structure Example (2)]

FIG. 7 illustrates a second mount structure example of the displaydevice of the first embodiment including the liquid crystal panel 1, itsdriver circuit, and others described above. The second mount structureexample corresponds to a case in which the conductive layer 60 isprovided on the inner surface side of the facing substrate 20 in thefirst embodiment and the first and second modification examples of thefirst embodiment. In the second mount structure example, one end of thelower electrode 32 and one end of the conductive layer 60 areelectrically connected to each other by a conductive part 191 in aregion FA serving as the frame part of the liquid crystal panel 1.

In the region FA serving as the frame part of the liquid crystal panel1, a sealing part 190 that connects between the array substrate 10 andthe facing substrate 20 and seals the liquid crystal layer 30 isprovided. The sealing part 190 is made of a predetermined sealingmaterial or others. Inside the sealing part 190 itself, a conductingpart 191 that conducts one end of the lower electrode 32 on the arraysubstrate 10 side and one end of the conductive layer 60 on the innersurface side on the facing substrate 20 side is provided. The conductingpart 191 can be made of a conductive material such as ITO or existingconductive particles. A thickness of the liquid crystal layer 30compared with those of the glass substrates 11 and 21 is practicallysmall.

Note that the sealing part 190 and the conducting part 191 may beseparated and provided at different positions from each other in the Xor Y direction. For example, the conducting part 191 may be provided atan inner position than the sealing part 190 of the liquid crystal panel1, that is, an inner position of the liquid crystal panel 1 in the X orY direction. In other words, the conducting part 191 may be provided ata position closer to a center side of the liquid crystal panel 1 thanthe sealing part 190 in the planar view. The lower electrode 32 and theconductive layer 60 have the same potential by applying the voltage V0from the driver side to, for example, one end of the lower electrode 32of the lower electrode 32 and the conductive layer 60 which are twoelectrodes conducted to each other by the conducting part 191. In otherwords, in the pixel writing period in the pixel display, for example,the voltage V0 is applied from the upper/lower-electrode driver 113 (seeFIG. 1) to the lower electrode 32, and the voltage V0 is applied fromthe upper/lower-electrode driver 113 to the conductive layer 60.

[Structure Example of Upper Electrode and Lower Electrode]

FIG. 8 illustrates a structure example of the upper electrode 31 and thelower electrode 32 applicable to the first embodiment and the first tothird modification examples of the first embodiment. Note that FIG. 8illustrates a schematic shape for three pixels of R, G, and B. A firstrubbing direction Rub and a direction in which the slit S extends, thatis, an extending direction of the slit S, are in parallel to the Xdirection. For example, the structure A and the structure α are adoptedin the first embodiment, while the structure B and the structure β areadopted in the first modification example of the first embodiment.

In the structure A, it is assumed that the upper electrode 31 isreferred to an upper electrode 31A and the lower electrode 32 isreferred to a lower electrode 32A. At this time, in the structure A, theupper electrode 31A is the pixel electrode PIX, and the lower electrode32A is the common electrode COM. The upper electrode 31A serving as thepixel electrode PIX is formed for each pixel. A shape of the upperelectrode 31A formed for each pixel is a rectangular shape. In the upperelectrode 31A, an opening 50 including a plurality of slits S is formed.Also, at, for example, a portion on one side of the upper electrode 31Ain the Y direction, a connecting part 1001 to be connected to a drainterminal of the TFT part is provided. The lower electrode 32A serving asthe common electrode COM is a solid layer formed on a region including aplurality of pixels such as the entire screen. Also, a conduction hole1002 is formed for each pixel in the lower electrode 32A so as tocorrespond to the position of the connecting part 1001 formed for eachpixel in the upper electrode 31A.

In the structure B, it is assumed that the upper electrode 31 isreferred to as an upper electrode 31B and the lower electrode 32 isreferred to as a lower electrode 32B. At this time, in the structure B,the upper electrode 31B is the common electrode COM, and the lowerelectrode 32B is the pixel electrode PIX. The upper electrode 31Bserving as the common electrode COM is a solid layer formed on a regionincluding a plurality of pixels such as the entire screen. Also, in theupper electrode 31B, an opening 50 including the slits S are formed foreach pixel. The lower electrode 32B serving as the pixel electrode PIXis formed for each pixel. A shape of the lower electrode 32B is arectangular shape. Also, at, for example, a portion on one side of thelower electrode 32B in the Y direction, a protruding part serving as aconnecting part 1001 to be connected to a drain terminal of the TFT partis provided.

As the shapes of the upper electrode 31, the lower electrode 32, and theopening 50 on the X-Y plane, the structure α has an alternate both-sidecomb teeth shape formed of the slits S extending in the X direction, andthe structure β3 has a one-side comb teeth shape formed of the slits Sextending in the X direction.

Items (a) and (b) of FIG. 9 illustrate structure examples of the upperelectrode 31, the lower electrode 32, and the opening 50 for each pixelin the case of the structure A. The item (a) of FIG. 9 illustrates theupper electrode 31A serving as the pixel electrode PIX in the case ofthe structure A and the structure α. The item (b) of FIG. 9 illustratesthe upper electrode 31A serving as the pixel electrode PIX in the caseof the structure A and the structure β3.

The upper electrode 31A serving as the pixel electrode PIX of the item(a) of FIG. 9 has a both-side comb teeth shape in the opening 50 asillustrated therein, the both-side comb teeth shape being obtained byalternately providing the plurality of slits S in the X direction onboth left and right sides in the X direction of the opening serving as aY-direction axis. Compared with the opening in the Y direction, one endsides of the plurality of left and right slits S are commonly connectedto each other as being opened. In other words, the opening 50 includes acommunicating opening 50 a, a plurality of slits Sa, and a plurality ofslits Sb. The communicating opening 50 a extends in the Y direction.Each of the plurality of slits Sa is connected to one side of thecommunicating opening 50 a in the X direction, is extended in the Xdirection, and is aligned in the Y direction. Each of the plurality ofslits Sb is connected to the other side of the communicating opening 50a in the X direction, is extended in the X direction, and is aligned inthe Y direction. And, the opening 50 is formed in the both-side combteeth shape so that the slits Sa and the slits Sb are alternatelyconnected to the communicating opening 50 a.

A shape of an electrode part of the upper electrode 31A is a shape inwhich comb teeth “K” which are a plurality of protruding parts in the Xdirection extend from each of left and right sides of the rectangle tothe inside of the pixel. In other words, the upper electrode 31Aincludes an extending part 31C, an extending part 31D, a plurality ofcomb teeth Ka, and a plurality of comb teeth Kb. The extending part 31Cextends in the Y direction. The extending part 31D extends in the Ydirection, and face the extending part 31C. Each of the plurality ofcomb teeth Ka protrudes from the extending part 31C to the extendingpart 31D, and is aligned in the Y direction. Each of the plurality ofcomb teeth Kb protrudes from the extending part 31D to the extendingpart 31C, and is aligned in the Y direction.

Also, in the example illustrated in the item (a) of FIG. 9, each shapeof the comb teeth K and the slits S is a trapezoidal shape in a planarview. Note that a lower side in the Y direction of the item (a) of FIG.9 is closed by the electrode part of the upper electrode 31A. However,the lower side may be opened. In other words, in the example illustratedin the item (a) of FIG. 9, the upper electrode 31A includes an extendingpart 31E extending in the X direction and connecting between an end ofthe extending part 31C on an opposite side of the connecting part 1001side and an end of the extending part 31D on an opposite side of theconnecting part 1001 side. And, the opening 50 is not connected to theoutside of the upper electrode 31A on the side opposite to theconnecting part 1001 side of the opening 50. However, the extending part31E may be not provided, and the opening 50 may be connected to theoutside of the upper electrode 31A.

The upper electrode 31A serving as the pixel electrode PIX of the item(b) of FIG. 9 has the one-side comb teeth shape so that the comb teeth Kwhich are the plurality of protruding parts in the X direction protrudeleftward from the side extending in the Y direction and being positionedon the right side of the rectangular shape in the X direction. In otherwords, the upper electrode 31A includes an extending part 31D and theplurality of comb teeth K. The extending part 31D extends in the Ydirection. Each of the plurality of comb teeth K is protruded from theextending part 31D to one side in the X direction, is extended in the Xdirection, and is aligned in the Y direction. And, the upper electrode31A is formed in the one-side comb teeth shape.

Also, the opening 50 has a the shape in which the plurality of slits Sextending in the X direction are connected to a right side of theopening extending in the Y direction and being positioned on the leftside thereof in the X direction. One end side of each of the pluralityof slits S is commonly opened. In other words, the opening 50 includes acommunicating opening 50 a and the plurality of slits S. Thecommunicating opening 50 a extends in the Y direction. Each of theplurality of slits S is connected to the other side of the communicatingopening 50 a in the X direction, is extended in the X direction, and isaligned in the Y direction. And, the opening 50 has the one-side combteeth shape. Also, in the example illustrated in the item (b) of FIG. 9,each shape of the comb teeth K and the slits S is a rectangular shape inthe planar view.

In the items (a) and (b) of FIG. 9, the opening 50 is an opening for thewhole pixel formed by the overlap of the upper electrode 31A serving asthe pixel electrode PIX and the lower electrode 32A serving as thecommon electrode COM (see FIG. 8). The opening 50 is a portion in aregion between the electrode parts of the upper electrode 31A in the X-Yplanar view, the portion where the upper electrode 31A serving as thepixel electrode PIX does not overlap above the lower electrode 32Aserving as the common electrode COM. Note that the opening 50 does notmean an effective region for the display in the pixel region. The slitsS are slits each extending in the X direction, in other words, openings,gaps, or others. Each slit S is formed of a pair of comb teeth Kadjacent to each other in the Y direction.

Items (a) and (b) of FIG. 10 illustrate structure examples of the upperelectrode 31B and the opening 50 for each pixel in the case of thestructure B. The item (a) of FIG. 10 illustrates the upper electrode 31Bserving as the common electrode COM in the case of the structure B andthe structure α. The item (b) of FIG. 10 illustrates the upper electrode31B serving as the common electrode COM in the case of the structure Band the structure β3.

The upper electrode 31B serving as the common electrode COM of the item(a) of FIG. 10 has an alternate both-side comb teeth shape in theopening 50 as illustrated therein as similar to that of the opening 50of the upper electrode 31A of the item (a) of FIG. 9. That is, theopening 50 includes a communicating opening 50 a, a plurality of slitsSa, and a plurality of slits Sb. The communicating opening 50 a extendsin the Y direction. Each of the plurality of slits Sa is connected toone side of the communicating opening 50 a in the X direction, isextended in the X direction, and is aligned in the Y direction. Each ofthe plurality of slits Sb is connected to the other side of thecommunicating opening 50 a in the X direction, is extended in the Xdirection, and is aligned in the Y direction. And, the opening 50 isformed in the both-side comb teeth shape so that the slits Sa and theslits Sb are alternately connected to the communicating opening 50 a. Onthe other hand, the upper electrode 31B includes an extending part 31C,an extending part 31D, a plurality of comb teeth Ka, and a plurality ofcomb teeth Kb. The extending part 31C extends in the Y direction. Theextending part 31D extends in the Y direction, and face the extendingpart 31C. Each of the plurality of comb teeth Ka protrudes from theextending part 31C to the extending part 31D, and is aligned in the Ydirection. Each of the plurality of comb teeth Kb protrudes from theextending part 31D to the extending part 31C, and is aligned in the Ydirection.

The upper electrode 31B serving as the common electrode COM of the item(b) of FIG. 10 has the one-side comb teeth shape in the opening 50 asillustrated therein as similar to the opening 50 of the upper electrode31A of the item (b) of FIG. 9. That is, the upper electrode 31B includesthe extending part 31C, an extending part 31D, and the plurality of combteeth K. The extending part 31C extends in the Y direction. Theextending part 31D extends in the Y direction, and face the extendingpart 31C. Each of the plurality of comb teeth K is protruded from theextending part 31D to the extending part 31C, is extended in the Xdirection, and is aligned in the Y direction. And, the upper electrode31B is formed in the one-side comb teeth shape. On the other hand, theopening 50 includes a communicating opening 50 a and the plurality ofslits S. The communicating opening 50 a is formed so as to be adjacentto the extending part 31C on the extending part 31D side and so as toextend in the Y direction. Each of the plurality of slits S is connectedto the communicating opening 50 a on the extending part 31D side, isextended in the X direction, and is aligned in the Y direction. And, theopening 50 has the one-side comb teeth shape.

Note that the upper and lower sides in the Y direction in the items (a)and (b) of FIG. 10 are closed by the electrode part of the upperelectrode 31B. However, they may be opened. In other words, in theexamples illustrated in the items (a) and (b) of FIG. 10, the upperelectrode 31B includes an extending part 31E and an extending part 31F.The extending part 31E extends in the X direction, and connects betweenthe extending part 31C and the extending part 31D on one sides of theplurality of comb teeth K in the Y direction. The extending part 31Fextends in the X direction, and connects between the extending part 31Cand the extending part 31D on the other sides of the plurality of combteeth K in the Y direction. And, the opening 50 is not connected to anopening formed in an adjacent pixel in the Y direction. However, eitheror both of the extending parts 31E and 31F may not be provided, and theopening 50 may be connected to the opening formed in the adjacent pixelin the Y direction.

Note that the actual numbers, sizes, and others of comb teeth K andslits S are adjusted in accordance with the pixel design. Also, thepresent invention is not limited to the aspect described above, andaspects of various combinations are possible. For example, each shape ofthe comb teeth K and the slits S in the structure α may be a rectangularshape, or each shape of the comb teeth K and the slits S in thestructure β may be a trapezoidal shape.

[Planar Structure Example (1)]

FIG. 11A illustrates a planar structure example on the X-Y plane of apixel, that is, a cell in the structure A and the structure α so as tocorrespond to the liquid crystal panel 1 of the second modificationexample of the first embodiment. FIG. 11A illustrates three pixels forR, G, and B. As illustrated in the drawing, the first rubbing directionRub which is a rubbing direction on the array substrate 10 side is inparallel to the X direction which is the extending direction of theslits S as a direction from left to right in the drawing.

On the array substrate 10 side, a plurality of gate lines 41 serving aselectrode lines in parallel to the X direction and a plurality of datalines 42 serving as electrode lines in parallel to the Y direction areprovided, and these gate lines 41 and data lines 42 cross each other sothat a plurality of pixels are partitioned. Such each of pixel is alsoreferred to as a sub-pixel. In the X-Y planar view, a shape of thepixel, that is, a shape of the opening except for the light-shieldingfilm 22 portion is a longitudinally-elongated rectangular shape so thata length in the Y direction is longer than a length in the X direction.Such a shape corresponds to an RGB stripe arrangement as the pixelarrangement.

Each of the pixels is explained below. A TFT part 43 is arranged invicinity of a crossing region where the gate line 41 and the data line42 cross each other. In the present example, the TFT part 43 is arrangedon an upper-left side on the sheet with respect to the pixel. The TFTpart 43 includes a TFT element, and the data line 42 is connected to asource terminal of the TFT element, the gate line 41 is connected to agate terminal of the TFT element, and the pixel electrode PIX isconnected to a drain terminal of the TFT element.

The light-shielding film 22 includes a transverse light-shielding filmpart 22A in parallel to the X direction and a longitudinallight-shielding film part 22B in parallel to the Y direction, andpartitions the pixels into a lattice shape. The transverselight-shielding film part 22A is arranged to overlap the gate line 41and the TFT part 43 when viewed from the Z direction. The longitudinallight-shielding film part 22B is arranged to overlap the data line 42when viewed from the Z direction.

The color filter 23 is a layer for color separation of the transmittedlight of the liquid crystal layer 30, and is formed of color filters 23r, 23 g, and 23 b which are layers classified to be colored into R(red), G (green), and B (blue), respectively, for each pixel line in theY direction correspondingly to the pixel arrangement. Note that a deltaarrangement, a diagonal arrangement, and a rectangle arrangement arealso possible as other pixel arrangements. Further, the number of colortypes of the color filter 23 is not limited to the three colors of R, G,and B, and may be one, two, four, or others.

In the pixel of FIG. 11A, the upper electrode 31 serving as the pixelelectrode PIX has the opening 50 having the alternate both-side combteeth shape as illustrated in the item (a) of FIG. 9. In accordance withthe pixel arrangement described above, for example, in the case of thesecond modification example of the first embodiment, the lower electrode32 which is the solid layer serving as the common electrode COM and thelattice-shaped light-shielding film 22 on one side of the lowerelectrode 32 in the Z direction, that is, above the lower electrode 32,are set to have the same potential as each other. In this manner, theliquid crystal orientation is stabilized in a lattice-shaped regionwhere the light-shielding film 22 is formed and a region in vicinity ofthe light-shielding film 22 on the X-Y plane. For example, the liquidcrystal orientation is stabilized also in the slits S arranged in thepixel region adjacent to the side of the transverse light-shielding filmpart 22A.

A rubbing process for the anti-parallel orientation is performed to theorientation layers, that is, the first and second orientation films sothat the orientation state of the liquid crystal of the liquid crystallayer 30 obtained when no potential difference is provided between theupper electrode 31 and the lower electrode 32, that is, the initialorientation state is a predetermined orientation state supporting thehigh-speed transverse electric filed mode. The first orientation filmbetween the liquid crystal layer 30 and the electrode layer includingthe upper electrode 31 and the lower electrode 32 on the array substrate10 side is subjected to the rubbing process in the first rubbingdirection Rub parallel to the X direction which is the extendingdirection of the slits S. The first rubbing direction Rub is a directionfrom left to right in the drawing. The second orientation film betweenthe liquid crystal layer 30 and the facing substrate 20 is subjected tothe rubbing process in a second rubbing direction opposite to the firstrubbing direction Rub for the first orientation film. The liquid crystalof the liquid crystal layer 30 is made of, for example, nematic liquidcrystal having negative dielectric anisotropy. In this case, the firstrubbing direction Rub on the array substrate 10 side is set as adirection substantially parallel to the X direction which is theextending direction of the slits S as described above. Note that, ifnematic liquid crystal having a positive dielectric anisotropy is used,the first rubbing direction Rub is set as a direction substantiallyorthogonal to the X direction which is the above-described extendingdirection of the slits S. Note that the first rubbing direction Rub isnot limited to the direction completely parallel or orthogonal to the Xdirection which is the extending direction of the slits S. As an angleformed by the X direction with the first rubbing direction Rub, an angleto some degrees such as 1 degree is allowable.

[Planar Structure Example (2)]

FIG. 11B illustrates a planar structure example of a pixel on the X-Yplane in the case of the structure A and the structure β, correspondingto the liquid crystal panel 1 of the second modification example of thefirst embodiment or others. In the pixel of FIG. 11B, the upperelectrode 31 serving as the pixel electrode PIX has the opening 50having the one-side comb teeth shape described by using the item (b) ofFIG. 9.

In accordance with the pixel structure described above, in the case of,for example, the second modification example of the first embodiment,the lower electrode 32 serving as the common electrode COM and thelattice-shaped light-shielding film 22 on one side of the lowerelectrode 32 in the Z direction, that is, above the lower electrode 32,are set to have the same potential. In this manner, on the X-Y plane,the orientation of the liquid crystal is stabilized in thelattice-shaped region where the light-shielding film 22 is formed andthe region in the vicinity of the light-shielding film 22.

[Planar Structure Example (3)]

FIG. 11C illustrates a planar structure example of a pixel on the X-Yplane in the case of the structure B and the structure α, correspondingto the first modification example of the first embodiment or others. Inthe pixel of FIG. 11C, the upper electrode 31 serving as the commonelectrode COM has the opening 50 having the alternate both-side combteeth shape described by using the item (a) of FIG. 10.

In accordance with the pixel structure described above, in the case of,for example, the first modification example of the first embodiment, theupper electrode 31 serving as the common electrode COM and thelattice-shaped light-shielding film 22 on one side of the upperelectrode 31 in the Z direction, that is, above the upper electrode 31,are set to have the same potential. In this manner, on the X-Y plane,the orientation of the liquid crystal is stabilized in thelattice-shaped region where the light-shielding film 22 is formed andthe region in the vicinity of the light-shielding film 22.

[Planar Structure Example (4)]

FIG. 11D similarly illustrates a planar structure example of a pixel onthe X-Y plane in the case of the structure B and the structure β,corresponding to the first modification example of the first embodimentor others. In the pixel of FIG. 11D, the upper electrode 31 serving asthe common electrode COM has the opening 50 having the one-side combteeth shape as illustrated in the item (b) of FIG. 10.

In accordance with the pixel structure described above, in the case of,for example, the first modification example of the first embodiment, theupper electrode 31 serving as the common electrode COM and thelattice-shaped light-shielding film 22 on one side of the upperelectrode 31 in the Z direction, that is, above the upper electrode 31,are set to have the same potential. In this manner, on the X-Y plane,the orientation of the liquid crystal is stabilized in thelattice-shaped region where the light-shielding film 22 is formed andthe region in the vicinity of the light-shielding film 22.

[Regarding Method of Driving Liquid Crystal]

In the liquid crystal panel 1 of any of the first embodiment and thefirst to third modification examples of the first embodiment, theopening 50 including the plurality of slits S is formed in the electrodelayer including the upper electrode 31 and the lower electrode 32 asillustrated in FIGS. 8 to 10 and 11A to 11D. As illustrated in FIGS. 8to 10 and 11A to 11D, the slits S extend in the transverse directioncorresponding to a horizontal direction of the screen, that is, in the Xdirection. The high-speed transverse electric field mode which is amethod of driving the liquid crystal supporting this electrode layer andthe opening 50 is a method for achieving high-speed responsiveness andothers by the orientation process for the anti-parallel orientationsupporting the X direction which is the extending direction of the slitsS. Details about this high-speed transverse electric field mode will bedescribed later by using FIGS. 13 to 15.

And, in the first embodiment and the first to third modificationexamples of the first embodiment, for example, the same voltage V0 isapplied in the usage of the liquid crystal display function so that thetwo types of layers of the lower electrode 32 and the conductive layer60 have the same potential. In this manner, in the X-Y planar view, theorientation stability of the liquid crystal can be improved in regionsincluding vicinity of the conducive layer 60. In other words, in the X-Yplanar view, the orientation of the liquid crystal can be stabilized inthe region where the conductive layer 60 is formed and the region in thevicinity of the conductive layer 60. That is, the response speed in thepixel display can be increased, and the display quality can be improved.

FIG. 12 illustrates arrangement patterns such as overlap in X, Y, and Zspaces regarding the upper and lower electrodes 31 and 32, and the lowerelectrode 32 and the conductive layer 60 to be provided with the samepotential. Hereinafter, the orientation stability of the liquid crystalin accordance with the patterns will be described. A pattern p1 is apattern in which the upper electrode 31, the lower electrode 32, and theconductive layer 60 overlap each other when viewed from the Z direction.A pattern p2 is a pattern in which the lower electrode 32 and theconductive layer 60 overlap each other when viewed from the Z direction,and a pattern p3 is a pattern in which the upper electrode 31 and theconductive layer 60 overlap each other when viewed from the Z direction.A reference symbol “f” simply represents the fringe electric fieldcaused in the opening 50 and the liquid crystal layer 30. The patternsp1, p2, and p3 are referred to as a pattern “pA”. At this time, in eachof the patterns p1, p2, and p3 as the pattern pA, the function andeffect of stabilizing the orientation of the liquid crystal is obtainedin a space between the lower electrode 32 and the conductive layer 60 tobe provided with the same potential.

Also, patterns p4, p5, and p6 are referred to as a pattern “pB”. At thistime, a pattern of the upper electrode 31 and the lower electrode 32 ineach of the patterns p4, p5, and p6 as the pattern pB is similar to thepattern of the upper electrode 31 and the lower electrode 32 in each ofthe patterns p1, p2, and p3 forming the pattern pA. On the other hand,in the pattern pB, while the upper electrode 31, the lower electrode 32,and the conductive layer 60 do not directly overlap each other whenviewed from the Z direction as different from the pattern pA, thepattern pB is a pattern in which the upper electrode 31, the lowerelectrode 32, and the conductive layer 60 are adjacent to each other inthe X and Y directions when viewed from the Z direction. In other words,the pattern pB is a pattern in which the upper electrode 31 and thelower electrode 32 exist in a region adjacent to the conductive layer 60in the X-Y planar view. Also in the pattern pB, in each of the patternsp4, p5, and p6 forming the pattern pB, the function and effects ofstabilizing the orientation of the liquid crystal is obtained in thespace between the lower electrode 32 and the conductive layer 60 to beprovided with the same potential, that is, in the regions including theregion in the vicinity of the conductive layer 60. In other words, theeffects of stabilizing the orientation of the liquid crystal is obtainedin the region where the conductive layer 60 is formed and the region inthe vicinity of the conductive layer 60.

[High-Speed Transverse Electric Field Mode]

By using FIGS. 13 to 15, liquid crystal orientation of the liquidcrystal layer 30 in the high-speed transverse electric field mode of thefirst embodiment and the first to third modification examples of thefirst embodiment is described. In other words, the orientation state ofthe liquid crystal of the liquid crystal layer 30 in the high-speedtransverse electric field mode of the first embodiment and the first tothird modification examples of the first embodiment is described byusing FIGS. 13 to 15.

FIG. 13 illustrates a structure example of the electrode part, theopening 50, and others of the pixel on the X-Y plane so as to correspondto the case of the structure a of FIG. 8. The structure illustrated inFIG. 13 is a structure in which the upper electrode 31 is the commonelectrode COM and in which the lower electrode 32 is the pixel electrodePIX. The lower electrode 32 serving as the pixel electrode PIX is arectangular electrode provided for each pixel. The upper electrode 31serving as the common electrode COM has the electrode part having theboth-side comb teeth shape obtained by alternately providing theplurality of comb teeth K which are the protruding parts extending inthe X direction with respect to a longitudinal-direction electrode part58 described later. The opening 50 is formed between the electrode partsof the upper electrode 31 serving as the common electrode COM. Assimilar to the above description, the opening 50 has the alternateboth-side comb teeth shape having the plurality of slits S extending inthe X direction.

Each of the slits S extending in the X direction is, for example, arectangular-shaped opening having a long side with a predeterminedlength and a short side with a predetermined width. In a plane facing asurface of the lower electrode 32 serving as the pixel electrode PIX inthe Z direction, the plurality of slits S are arranged so as to have thesame shape and are aligned in the X direction which is the extendingdirection. In other words, the plurality of slits S extend in the Xdirection and are aligned in the Y direction. In the X-Y planar view,the opening 50 for each pixel corresponds to the region where the upperelectrode 31 serving as the common electrode COM does not overlap thelower electrode 32 in the region where the lower electrode 32 serving asthe pixel electrode PIX is formed.

A reference symbol 58 represents an electrode part extending in alongitudinal direction, that is, the Y direction, in the electrode partof the upper electrode 31 having the both-side comb teeth shape, and isreferred to as a longitudinal-direction electrode part. The comb teethKa are protruding parts of the comb teeth K each protruding to one sideof the longitudinal-direction electrode part 58 in the X direction, eachextending in the X direction, and being aligned in the Y direction.Also, the comb teeth Kb are protruding parts of the comb teeth K eachprotruding to the other side of the longitudinal-direction electrodepart 58 in the X direction, each extending in the X direction, and beingaligned in the Y direction. To the longitudinal-direction electrode part58, one ends of the plurality of comb teeth Ka and Kb on both ends inthe X direction are connected. A shape of the upper electrode 31 is theboth-side comb teeth shape in which the comb teeth Ka and Kb arealternately protruded in the X direction toward both sides withcentering on the longitudinal-direction electrode part 58. The slits Sare formed of a pair of the comb teeth K adjacent to each other in the Ydirection.

A reference symbol 57 represents a communication opening of the opening50 extending in the longitudinal direction, that is, the Y direction,and is referred to as a longitudinal-direction slit. The slit Sa is aslit of the slits S being connected to one side of thelongitudinal-direction slit 57 in the X direction and extending in the Xdirection, and the slit Sb is a slit of the slits S being connected tothe other side of the longitudinal-direction slit 57 in the X directionand extending in the X direction. By connecting the plurality of slitsSa and slits Sb to the longitudinal-direction slit 57, a continuousopening is formed. One end of the slit Sa in the X direction is closedby the upper electrode 31 serving as the electrode part, and the otherend of the slit Sa in the X direction is opened, that is, connected tothe longitudinal-direction slit 57. One end of the slit Sb in the Xdirection is opened, that is, connected to the longitudinal-directionslit 57, and the other end of the slit Sb in the X direction is closedby the upper electrode 31 serving as the electrode part. A shape of theopening 50 is the both-side comb teeth shape in which the slit Sa andthe slit Sb are alternately protruded in the X direction toward bothsides with centering on the longitudinal-direction slit 57.

Between the plurality of slits S being at the same position in the Xdirection and aligned in the Y direction, the positions of both ends ofthe slits S in the X direction are equalized with each other, so thatshapes of the plurality of slits S are the same shape as each other.Also, the plurality of slits S aligned in the Y direction are arrangedwith a constant pitch in the Y direction. In other words, the pluralityof slits S aligned in the Y direction are aligned with the same intervalin the Y direction. Also, with centering on the longitudinal-directionslit 57, groups of slits S in adjacent rows to each other in the Xdirection on left and right are arranged so that the plurality of slitsS are alternately shifted from each other in the Y direction. In otherwords, the slit Sa and the slit Sb are connected to thelongitudinal-direction slit 57 so as to be alternately shifted from eachother. A degree of this shift is, for example, ½ of the pitch betweenthe slits S in the Y direction. This alternate shape is similar in theelectrode part of the upper electrode 31. That is, the comb teeth Ka andKb are connected to the longitudinal-direction electrode part 58 so asto be alternately shifted from each other. The alternate both-side combteeth shape of the electrode part of the upper electrode 31 is, in otherwords, a shape in which the comb teeth K are arranged in zigzagarrangement. Also, the alternate both-side comb teeth shape of theopening 50 is, in other words, a shape in which the slits S are arrangedin zigzag (chidori shape in Japanese) arrangement.

In order to configure the liquid crystal display device of thehigh-speed transverse electric field mode in accordance with thestructure of the upper electrode 31 serving as the electrode part andthe opening 50, the rubbing process for the anti-parallel orientation isperformed for the first and second orientation films serving as theorientation films. That is, the first rubbing direction Rub in the firstorientation film on the array substrate 10 side is a directionsubstantially parallel to the slits S extending in the X direction, thatis, from left to right in the drawing, and the second rubbing directionin the second orientation film on the facing substrate 20 side is adirection opposite to the first rubbing direction Rub, that is, fromright to left in the drawing.

Also, in FIG. 13, each of reference symbols F1 and F2 represents eachregion of both side parts of the electrode forming the slit S extendingin the X direction. Further, the liquid crystal orientation in theregion F1 is different from the liquid crystal orientation in the regionF2. The region F1 surrounded by a solid line so as to represent one sidepart is a region where a rotating direction of the liquid crystalmolecules in the substrate plane, that is, in the X-Y plane is aclockwise direction, and the region F2 surrounded by a broken line so asto represent the other side part is a region where the rotatingdirection of the liquid crystal molecules is reversely acounterclockwise direction. The opening 50 has the alternate both-sidecomb teeth shape. Each slit S has a pair of long sides facing each otherin a width direction, that is, the Y direction. A region in vicinity ofthe long side on one side is the region F1, and a region in vicinity ofthe long side on the other side is the region F2. In viewing between therows of the slits S adjacent to each other in the X direction via thelongitudinal-direction slit 57 of the opening 50, that is, between therow of the slit Sa and the row of the slit Sb, the regions with the samerotating directions as each other among the regions F1 and F2 arearranged close to each other in the left and right slits S, that is, inthe slit Sa and the slit Sb, because of the alternately-shiftedarrangement.

That is, the same type of the regions among the regions F1 and F2 arearranged on the substantially same line in the X direction. In otherwords, the same type of the regions among the two types of the regionsF1 and F2 are lined on the same straight line extending in the Xdirection so as to be adjacent to each other in the X direction. In theY direction, the regions F1 and F2 which are the two types of regionsare alternately arranged. In other words, the regions F1 and F2 arealternately aligned in the Y direction. In this manner, the regions withthe same liquid crystal orientation, that is, the same type of theregions among the regions F1 and F2 are aligned so as to be lined in theX direction, and therefore, the orientation stability of the liquidcrystal is increased. In other words, the regions having the same liquidcrystal orientation among the regions F1 and F2 are aligned on the samestraight line extending in the X direction so as to be adjacent to eachother in the X direction in the planar view, and therefore, theorientation stability of the liquid crystal is increased.

In FIG. 13, note that a reference symbol “L0” represents a total lengthof the slit Sa and the slit Sb including the width of thelongitudinal-direction slit 57. The L1 and the L2 represent lengths ofthe slit Sa and the slit Sb as left and right slits S, respectively. Inother words, the length L0 is a total length of the length L1 of theslit Sa in the X direction, the width of the longitudinal-direction slit57 in the X direction, and the length L2 of the slit Sb in the Xdirection. Each of the length L1 of the slit Sa and the length L2 of theslit Sb is, for example, in the range of 10 to 60 μm. Also, in aviewpoint of the stabilization of the rotating direction of the liquidcrystal molecules, it is preferred that each of the lengths L1 and L2 isin the range of 40 μm or smaller. Each of the width of the slit Sa andthe width of the slit Sb is, for example, in the range of 2 to 5 μm, andeach of the pitch between the slits Sa and the pitch between the slitsSb is, for example, in the range of 4 to 10 μm. In order to increase theresponse speed, it is preferred that these widths and pitches are small.Also, when the length L1 of the slit Sa is set to 0, the opening 50 hasthe one-side comb teeth shape as the structure β.

Also FIG. 13 illustrates the case in which the shape of the opening 50is a shape which is continuously opened over the pixel line in the Ydirection without closing the opening 50 for each pixel. However, theshape of the opening 50 may be a shape in which the opening 50 is closedfor each pixel. Further, the shape of the opening 50 can be a shape inwhich the longitudinal-direction slit 57 is not provided, such as ashape in which the respective openings of the slits S are independentfrom each other in an island shape. However, by providing thelongitudinal-direction slit 57, the liquid crystal panel 1 can be moreeasily manufactured.

FIG. 14 is diagrams obtained by partially enlarging FIG. 13,illustrating images of the rotation of the liquid crystal molecules inthe regions F1 and F2 with the liquid crystal orientation in the twotypes of the rotating directions described above. An item (a) of FIG. 14illustrates an image of rotation when the voltage is OFF, that is, inthe initial orientation state, and an item (b) of FIG. 14 illustrates animage of rotation when the voltage is ON. In FIG. 14, note that the casein which the voltage is OFF is represented by a term “voltage OFF”, andthe case in which the voltage is ON is represented by a term “voltageON”. A reference symbol 701 denotes an image of the liquid crystalmolecules. As illustrated in the drawings, the regions F1 and F2represent vicinity regions including the both side parts of theelectrode forming the slit S, that is, vicinity regions centering on thelong sides facing each other in the Y direction which is the widthdirection of the slit Sa and the slit Sb. For example, the slit Saconnected to one side of the longitudinal-direction slit 57 in the Xdirection has a long side a1 on one side in the Y direction and a longside a2 on the other side in the Y direction. Also, each of the combteeth Ka serving as the protruding part arranged on one side of the slitSa in the X direction has a long side a3 on one side in the Y directionand a long side a4 on the other side in the Y direction. And, the longsides a1 and a3 in the X direction are aligned on the substantially sameline, and the long sides a2 and a4 in the X direction are aligned on thesubstantially same line. In other words, the long sides a1 and a3 arealigned on the same straight line extending in the X direction.

One end of the slit S in the X direction is closed by the upperelectrode 31 serving as the electrode part, and the other end of slit Sin the X direction is connected to the longitudinal-direction slit 57.In each long side such as the long sides a1 facing each other in the Ydirection which is the width direction of the slit S, one end side ofthe long side forms a corner closed by the electrode part of the upperelectrode 31, and the other end side thereof forms a corner opened tothe longitudinal-direction slit 57. Two long sides of one slit S formtwo corners at an intersection point with the longitudinal-directionslit 57. These corners have a function serving as an electric fieldcontrol part, that is, a function of stabilizing the liquid crystalorientation or the rotating direction. The orientation is stabilized atthese corners serving as the electric field control parts by setting therotating direction of the liquid crystal molecules to be, for example,clockwise in a region in vicinity of a line from the closed corner tothe opened corner in the long side such as the long side a1 of each slitS, that is, in the region F1. That is, the rotating directions of theliquid crystal molecules are the same as each other in the regions F1which are the regions in the vicinity of the long sides a1 and a3aligned on the line in the X direction, so that the orientation isstabilized. On the other hand, in the region F2 which is a region invicinity of the long side a2 adjacent to the long side a1 in the Ydirection, the rotating directions of the liquid crystal molecules areset to be, for example, counterclockwise, and are reverse to therotating directions in the region F1 which is the region in the vicinityof the long side a1 adjacent to the long side a2 in the Y direction.And, such regions F2 are aligned on a line in the X direction, so thatthe orientation is stabilized. As described above, in the opening 50having the alternate both-side comb teeth shape including thelongitudinal-direction slit 57, by providing the corner serving as theelectric filed control part to each slit S, the orientation stability ofthe liquid crystal of the pixel is increased.

One end of the slit S in the X direction is closed by the upperelectrode 31 serving as the electrode part, and the other end of theslit S in the X direction is connected to the longitudinal-directionslit 57. The rotating directions of the liquid crystal molecules are thesame as each other to be, for example, clockwise in the regions F1 whichare the regions in the vicinity of the long sides a1 and 3 aligned onthe same straight line extending in the X direction, so that theorientation of the liquid crystal is stabilized. On the other hand, therotating directions of the liquid crystal molecules are, for example,counterclockwise in the region F2 which is the region in the vicinity ofthe long side a2 adjacent to the long side a1 in the Y direction, andare reverse to the rotating directions of the liquid crystal moleculesin the region F1 which is the region in the vicinity of the long side a1adjacent to the long side a2 in the Y direction. And, such regions F2are aligned on the same line extending in the X direction, so that theorientation of the liquid crystal is stabilized.

In the voltage OFF state illustrated the item (a) of FIG. 14, in theliquid crystal of the liquid crystal layer 30, the long axes of therespective liquid crystal molecules are oriented along the same Xdirection in the regions F1 and F2 of the facing long sides of the slitS so as to correspond to the first rubbing direction Rub. The voltage isapplied to the upper electrode 31 and the lower electrode 32, so thatthe fringe electric field is caused on the electrode layer of the upperelectrode 31 and the lower electrode 32 including the opening 50, andtransition from the state shown in the item (a) to the state shown inthe item (b) of FIG. 14 is caused by the caused fringe electric field.At this time, the liquid crystal molecules of the liquid crystal layer30 rise so that the long axes of the liquid crystal molecules are alongthe Z direction as rotating, that is, twisting, in rotating directionsreverse to each other between the region F1 which is the region in thevicinity of the long side on one side of the two facing long sides ofeach slit S and the region F2 which is the region in the vicinity of thelong side on the other side thereof. Note that, in an intermediateregion between these two facing long sides of the slit S, the clockwiserotation and the counterclockwise rotation are mixed as the rotatingdirections of the liquid crystal molecules.

And, in the voltage ON state of the item (b) of FIG. 14, the rotationstates of the liquid crystal molecules in the regions F1 which are theregions in vicinity of the long sides a1 and a3 on one side of the twofacing long sides of each slit S are substantially equalized on the samestraight line extending in the X direction. Also, the rotation states ofthe liquid crystal molecules in the regions F2 which are the regions invicinity of the long sides a2 and a4 on the other side of the two facinglong sides of each slit S are substantially equalized on the samestraight line extending in the X direction. As described above, on theelectrode layer of the upper electrode 31 and the lower electrode 32including the opening 50, the orientations of the liquid crystalmolecules of the liquid crystal layer 30 are controlled so as to bedivided into the region F1 and the region F2 which are the regions withthe two types of the rotating directions. Accordingly, the responsespeed obtained when the voltage is applied to the upper electrode 31 andthe lower electrode 32 is increased.

FIG. 15 illustrates orientation states of the liquid crystal along anA1-A2 cross-sectional surface of FIG. 13. An item (a) of FIG. 15illustrates an orientation state of the liquid crystal obtained when thevoltage is OFF, that is, in the initial orientation state, and an item(b) of FIG. 15 illustrates an orientation state of the liquid crystalobtained when the voltage is ON. In FIG. 15, note that the case in whichthe voltage is OFF is represented by a term “voltage OFF”, and the casein which the voltage is ON is represented by a term “voltage ON”. In theitem (a) of FIG. 15, the liquid crystal molecules are oriented so as toalong a pretilt direction 800 for forming a predetermined pretilt anglewith the first rubbing direction Rub on the array substrate 10 side,that is, the direction from left to right in the drawing. In the liquidcrystal molecules, their positions in the Z direction at one end sidecorresponding to a proceeding direction side of the first rubbingdirection Rub, that is, to a right side in the drawing, are on one sidein the Z direction, that is, on an upper side in the drawing than theirpositions in the Z direction at the other end side corresponding to aleft side in the drawing. In the transition from the state of the item(a) of FIG. 15 to the state of the item (b) of FIG. 15, the liquidcrystal molecules rise so that the long axes of the liquid crystalmolecules are along the Z direction as rotating in the X-Y plane asillustrated in FIG. 14. In the item (b) of FIG. 15, a line “a”corresponds to a position of the longitudinal-direction slit 57 (seeFIG. 14). In a region 801 on the right side from the line “a” in thedrawing, the liquid crystal rises in a positive direction correspondingto the pretilt direction 800. In a region 802 on the left side from theline “a” in the drawing, the liquid crystal rises in an oppositedirection. That is, the liquid crystal molecules in the region 802 onthe left side in the drawing are more difficult to rise than those inthe region 801 on the right side in the drawing, and therefore, have adisadvantage in responsiveness.

Accordingly, more particularly in the case of the anti-parallelorientation, the length L1 of the slit Sa and the length L2 of the slitSb (see FIG. 13) in the opening 50 are changed so as to satisfy arelation “L1<L2” so that a ratio of the slit Sa which is a portionhaving the length L1 is decreased. In this manner, the disadvantage inresponsiveness in the region 802 on the left side in the drawing can bedecreased, and therefore, the response speed obtained when the voltageis applied to the upper electrode 31 and the lower electrode 32 can beincreased.

As illustrated in FIGS. 13 to 15, the liquid crystal panel of the firstembodiment is the liquid crystal panel of the high-speed transverseelectric field mode to which the rubbing process for the anti-parallelorientation is performed in the direction parallel to the X directionwhich is the extending direction of the slits S in accordance with thestructure such as the alternate both-side comb teeth shape having theslits S extending in the X direction in the opening 50. In the presentmethod, when the voltage is applied to the upper electrode 31 and thelower electrode 32, orientation is made so that, the liquid crystalmolecules are oriented so as to rise in the Z direction as rotating inthe reverse directions from each other in the regions F1 and F2 servingas the vicinity regions of the long side on one side and the long sideon the other side among the two long sides facing each other in the Ydirection which is the width direction of the slit S extending in the Xdirection of the opening 50. By this high-speed transverse electricfield mode, the response speed of the pixel obtained when the voltage isapplied to the upper electrode 31 and the lower electrode 32 isincreased, that is, the response time is shortened, and the displayquality is enhanced.

<Second Embodiment>

In the first embodiment, the case in which the technique found by theinventor of the present application is applied to a liquid crystaldisplay device and an electronic apparatus has been described. Bycontrast, in a second embodiment, a case in which the technique found bythe inventor of the present application is applied to a liquid crystaldisplay device with a liquid crystal touch sensor and an electronicapparatus equipped therewith will be described.

[Principle of Touch Sensor]

First, a principle of a touch sensor will be described. FIG. 16illustrates a principle of a mutual capacity type of a capacitive touchsensor TS that is applicable to a liquid crystal touch panel 2 (see FIG.17 described later) of the second embodiment. An item (a) of FIG. 16illustrates a structure of the touch sensor TS. An item (b) of FIG. 16illustrates an equivalent circuit of the item (a) of FIG. 16. An item(c) of FIG. 16 illustrates an example of a signal, that is, a voltageobtained in touch detection by the touch sensor TS of the item (a) ofFIG. 16. In the item (a) of FIG. 16, the touch sensor TS has a touchdrive electrode E1 and a touch detection electrode E2 arranged so as toface each other and interpose a dielectric body DE therebetween, so thata capacitance C1 for the touch detection is formed by them. Note thatthe touch drive electrode E1 corresponds to a transmission-sideelectrode 71 (see FIG. 18 described later), and the touch detectionelectrode E2 corresponds to a reception-side electrode 72 (see FIG. 18described later). The touch sensor TS detects either a touch ornon-touch state, that is, either an ON or OFF state by using change ofthe capacitance C1 caused by approach or touch of a conductive body Msuch as a finger on a surface on the touch detection electrode E2 side.

One end of the capacitance C1 in the item (b) of FIG. 16 on the touchdrive electrode E1 side is connected to an alternating-current signalsource AS, and a point “p” at the other end on the touch detectionelectrode E2 side is grounded via a resistor “R” and is connected to avoltage detector DET. When the touch sensor TS is operated, an inputsignal “s1” in the item (c) of FIG. 16 is applied from thealternating-current signal source As to the touch drive electrode E1.The input signal s1 is a touch drive signal. When the input signal s1 isapplied, a current “I1” flows via the capacitance C1 of the touch sensorTS, and an output signal “s2” of the item (c) of FIG. 16 is detected bythe voltage detector DET on the touch detection electrode E2 side.

In the item (c) of FIG. 16, the input signal s1 is a voltage formed ofan alternating-current square wave having a predetermined frequency. Theoutput signal s2 is changed so as to be a voltage V1 in the non-touchstate, that is, in the OFF state, and to be a voltage V2 in the touchstate, that is, in the ON state. The non-touch state represents a statethat the conductive body M is not approaching or touching the touchdetection electrode E2 on a front surface side of the touch sensor TS.The touch state represents a state that the conductive body M isapproaching to or touching the touch detection electrode E2 on the frontsurface side of the touch sensor TS. In the non-touch state, that is,the OFF state, during the application of the input signal S1, thecurrent I1 in accordance with a value of the capacitance C1 is flowed bycharge/discharge of the capacitance C1, and the voltage detected by thevoltage detector DET becomes the voltage V1 of the output signal s2 ofthe item (c) of FIG. 16. In the item (c) of FIG. 16, the ON state isrepresented by a term “ON”, and the OFF state is represented by a term“OFF”.

In the touch state, that is, the ON state, a capacitance C2 formed ofthe conductive body M is additionally connected in series to thecapacitance C1. In this state, the current I1 and a current I2 inaccordance with values of the capacitances C1 and C2 are flowed bycharge/discharge of the capacitances C1 and C2, respectively, and thevoltage detected by the voltage detector DET becomes a voltage V2 of theoutput signal s2 of the item (c) of FIG. 16. A potential of a point “p”on the touch detection electrode E2 side in the touch state, that is,the ON state, is a potential of a divided voltage defined by the valuesof the currents I1 and I2 in accordance with the values of thecapacitances C1 and C2, respectively. That is, the voltage V2 in thetouch state, that is, the ON state, is smaller than the voltage V1 inthe non-touch state, that is, the OFF state. A drive circuit for thetouch detection for supporting the voltage detector DET compares thevoltages V1 and V2 of the output signal s2 with a threshold voltage Vth,and detects the touch state, that is, the ON state, when, for example,the voltage V2 is smaller than the threshold voltage Vth. That is, theoutput signal s2 is a touch detection signal. Alternatively, the drivecircuit for the touch detection for supporting the voltage detector DETcompares a change amount from the voltage V1 to the voltage V2 with adifferent threshold from the threshold voltage, so that thetouch/non-touch states are detected.

Note that the liquid crystal touch panel 2 (see FIG. 17 described later)of the second embodiment is not limited to the mutual capacity type ofthe capacitive touch panel described above, and any type is applicableas long as the transmission-side electrode and the reception-sideelectrode serving as the conductive layers are used.

[Electronic Apparatus and Liquid Crystal Display Device]

FIG. 17 illustrates a block structure including a liquid crystal displaydevice 300 equipped with a touch sensor serving as a liquid crystaltouch panel module, which is the display device of the second embodimentand including an electronic apparatus 200 on which the liquid crystaldisplay device 300 equipped with the touch sensor is mounted. That is,the electronic apparatus 200 of the second embodiment includes theliquid crystal display device 300 equipped with the touch sensor servingas the liquid crystal touch panel module.

The liquid crystal display device 300 equipped with the touch sensor hasthe liquid crystal touch panel 2. Also, the liquid crystal displaydevice 300 equipped with the touch sensor has: a liquid crystal touchpanel driver 102 serving as a controller for main drive control; and agate driver 111, a data driver 112, an upper/lower-electrode driver 113,and a touch panel electrode driver 114 serving as drivers which aredrive circuits for respective electrode lines of the liquid crystaltouch panel 2.

The liquid crystal touch panel driver 102 controls a liquid crystaldisplay function and a touch panel function based on a control signaland data serving as control instruction information from the controlunit 201. Note that an aspect in which these functions are separatedfrom each other, and are mounted on different drivers, and are linked toeach other may be applicable. When the video display is controlled bythe liquid crystal display function, the liquid crystal touch paneldriver 102 provides the control signal and the data serving as thecorresponding control instruction information to each driver for thegate driver 111, the data driver 112, and the upper/lower-electrodedriver 113. Also, in the control by the touch panel function, the liquidcrystal touch panel driver 102 provides the control signal, the data,and others serving as the control instruction information to the touchpanel electrode driver 114, and receives information obtained by theabove-described touch detection signal from the touch panel electrodedriver 114.

The touch panel electrode driver 114 drives the transmission-sideelectrode 71 and the reception-side electrode 72 (see FIG. 18 describedlater) of the liquid crystal touch panel 2 so as to follow the controlfrom the liquid crystal touch panel driver 102. The touch panelelectrode driver 114 inputs the input signal s1, which is a touch drivesignal, to the transmission-side electrode 71, and detects the outputsignal S2 as a touch signal in response to the input signal inaccordance with the approach or touch of the conductive body M (see FIG.16) from the reception-side electrode 72. And, for example, the touchpanel electrode driver 114 determines the touch/non-touch state andcalculates a touch detection position based on the output signal s2 in atouch detection unit TU (see FIG. 18 described later) in a touch panelfunction layer on the screen. To the liquid crystal touch panel driver102, the touch panel electrode driver 114 outputs information of resultsof the determination and the calculation such as information of thetouching/non-touching and the touch detection position. Then, from theliquid crystal touch panel driver 102 to the control part 201, theinformation of the touch detection position and others are responded.Note that the calculation of the touch detection position and others maybe performed by the liquid crystal touch panel driver 102 or the controlpart 201.

[Structure Example of Touch Sensor (1)]

FIG. 18 illustrates a first structure example of the touch sensor forconfiguring the touch panel function for supporting the liquid crystaltouch panel of a second embodiment and a first modification example ofthe second embodiment described later. That is, FIG. 18 illustrates afirst structure example of the touch sensor provided to a liquid crystaldisplay device equipped with a touch sensor of the second embodiment. Areference symbol 80 represents a function layer of the touch sensor. Areference symbol TU represents the touch detection unit configured ofthe transmission-side electrode 71 and the reception-side electrode 72.In the function layer 80, a plurality of transmission-side electrodes 71extending in the X direction and aligning in the Y direction areprovided on a back surface side, and a plurality of reception-sideelectrodes 72 extending in the Y direction and aligning in the Xdirection are provided on a front surface side. In a planar view, anintersection region where each transmission-side electrode 71 and eachreception-side electrode 72 intersects each other is the touch detectionunit TU. In the planar view, for example, a plurality of pixels arearranged inside a region where one transmission-side electrode 71 isformed. Also, in the planar view, for example, a plurality of pixels arearranged inside a region where one reception-side electrode 72 isformed.

In the touch detection using the touch panel function, the input signals1 serving as the touch drive signal is sequentially inputted from thetouch panel electrode driver 114 (see FIG. 17) to each of the pluralityof transmission-side electrodes 71, so that each of the plurality oftransmission-side electrodes 71 is sequentially scan-driven. On theother hand, the output signal s2 serving as the touch detection signalis outputted from the plurality of reception-side electrodes 72, and theoutput signal s2 is detected by the touch panel electrode driver 114.The touch panel electrode driver 114 can detect thetouching/non-touching and the touch position in accordance with theapproach or the touch of the conductive body M based on a publicly-knowncalculation process based on the output signal s2.

[Structure Example of Touch Sensor (2)]

FIG. 19 illustrates a second structure example of the touch sensor forconfiguring the touch panel function for supporting the liquid crystaltouch panel of the second embodiment and the first modification exampleof the second embodiment described later. That is, FIG. 19 illustrates asecond structure example of the touch sensor provided to the liquidcrystal display device equipped with the touch sensor of the secondembodiment. In the second structure example illustrated in FIG. 19, thetransmission-side electrode 71 is formed of, for example, a solid layerformed in regions including the region where the plurality of pixels areformed, such as the region of the entire screen. The reception-sideelectrodes 72 are arranged in a matrix shape. In a planar view, aplurality of pixels are arranged in the matrix shape in the X and Ydirections inside, for example, the region where one reception-sideelectrode 72 is formed. In the planar view, a region where thereception-side electrode 72 overlaps the transmission-side electrode 71is the touch detection unit TU. Note that the transmission-sideelectrode 71 may be provided so as to correspond to each pixel or thetransmission-side electrode 71 may correspond to each block so that theplurality of pixels are regarded as one block.

In the touch detection using the touch panel function, the input signals1 serving as the touch drive signal is inputted from the touch panelelectrode driver 114 (see FIG. 17) to the transmission-side electrode71. On the other hand, the output signal s2 serving as the touchdetection signal is outputted from the plurality of reception-sideelectrodes 72 via a connect line, and the output signal s2 is detectedby the touch panel electrode driver 114. The touch panel electrodedriver 114 can detect the touch position or others based on the outputsignal s2 as similar to the first structure example.

[Liquid Crystal Touch Panel of Second Embodiment]

FIG. 20 illustrates a schematic structure of a cross-sectional surfaceof the liquid crystal touch panel 2 of the liquid crystal display deviceequipped with the touch sensor, which is the display device of thesecond embodiment. The liquid crystal touch panel 2 of the secondembodiment is such a liquid crystal touch panel 2 that thetransmission-side electrode 71 and the reception-side electrode 72forming the mutual capacity type of the electrostatic capacitive touchpanel function or touch sensor function are provided on the facingsubstrate 20 side in the liquid crystal panel 1A (see FIG. 2) of thefirst embodiment. Note that the liquid crystal touch panel 2 of thesecond embodiment is particularly referred to as a liquid crystal touchpanel 2A here. And, in the liquid crystal touch panel 2A of the secondembodiment, the lower electrode 32 serving as the common electrode COMon the array substrate side 10 and the transmission-side electrode 71 onthe facing substrate 20 side have the same potential as each other. Thatis, in the liquid crystal touch panel 2A of the second embodiment, thetransmission-side electrode 71 is provided as the conductive layersimilar to the conductive layer 60 (see FIG. 2) in the liquid crystalpanel 1A of the first embodiment.

Structure examples of the touch sensor formed of the transmission-sideelectrode 71 and the reception-side electrode 72 can be thoseillustrated in FIGS. 18 and 19. Also, the structure of the liquidcrystal display device equipped with the touch sensor including theliquid crystal touch panel 2 can be the structure illustrated in FIG.17. Further, an example of drive control of the liquid crystal touchpanel 2 including the transmission-side electrode 71 and thereception-side electrode 72 is illustrated in FIG. 22 described later.

Each of the upper electrode 31, the lower electrode 32, thetransmission-side electrode 71, and the reception-side electrode 72 isconfigured of a transparent electrode made of ITO or others. In thesecond embodiment, a layer of the transmission-side electrode 71 isprovided on an inner surface side of the glass substrate 21 included inthe facing substrate 20, and a layer of the reception-side electrode 72is provided on an outer surface side of the glass substrate 21 includedin the facing substrate 20. And, the layer of the transmission-sideelectrode 71 and the layer of the reception-side electrode 72 are set tohave the same potential as each other.

The transmission-side electrode 71 and the reception-side electrode 72are elements configuring the touch sensor function, and configure theillustrated capacitance C between the transmission-side electrode 71 andthe reception-side electrode 72. The touch sensor detects thetouch/non-touch state or others by using the change in the capacitance Ccaused by the approach or the touch of the conductive body M such as afinger on the surface of the reception-side electrode 72 on the frontsurface side of the facing substrate 20. The state with touching isreferred to as the ON state, and the state without touching is referredto as the OFF state.

Also, the transmission-side electrode 71 and the reception-sideelectrode 72 have not only the touch sensor function but also a functionas the electrostatic protective layer as described by using FIG. 5 inthe third modification example of the first embodiment. That is, thestatic electricity charged on the panel screen, in other words, on thefront surface side of the facing substrate 20 can be discharged by thetransmission-side electrode 71 and the reception-side electrode 72 viathe transmission-side electrode 71 or the reception-side electrode 72 tothe outside of the liquid crystal touch panel 2, that is, to the driverside or the ground.

In the image display, the lower electrode 32 and the transmission-sideelectrode 71 have the same potential as each other. Also, since thetouch panel function is achieved by the transmission-side electrode 71and the reception-side electrode 72, it is not necessary to maintain thesame potential between the lower electrode 32 and the transmission-sideelectrode 71 during when the transmission-side electrode 71 is used,that is, during the application of the touch drive signal to thetransmission-side electrode 71.

Note that the light-shielding film 22, the color filer 23, or othersdescribed in the second modification example of the first embodiment canbe further added onto the facing substrate 20 side in addition to theliquid crystal touch panel 2A of the second embodiment. In this case, assimilar to the second modification example of the first embodiment, thelight-shielding film 22 may be included in the two types of layers to beprovided with the same potential.

Also, as another aspect in the second embodiment, the lower electrode 32and the reception-side electrode 72 may have the same potential as eachother. Further, as still another aspect in the second embodiment, thelower electrode 32 and both of the transmission-side electrode 71 andthe reception-side electrode 72 may have the same potential as eachother.

Still further, the second embodiment shows a structure of a so-calledin-cell type in which the transmission-side electrode 71 and thereception-side electrode 72 are mounted inside the facing substrate 20of the liquid crystal panel. Meanwhile, as another example of the secondembodiment, the touch panel function layer configured of thetransmission-side electrode and the reception-side electrode may beadhered on the front surface side of the facing substrate 20. Also inthis case, the transmission-side electrode or the reception-sideelectrode in the touch panel function layer can be one of the two typesof layers to be provided with the same potential.

By the liquid crystal touch panel 2A of the second embodiment, theorientation of the liquid crystal is stabilized in the space between thelower electrode 32 and the transmission-side electrode 71 when theliquid crystal display function is used, that is, in the image displayon the screen, so that such an effect that the transmittance is improvedby the orientation stability of the liquid crystal can be obtained inthe regions including the region including the transmission-sideelectrode 71 in the X-Y planar view. In other words, in the X-Y planarview, such an effect that the orientation of the liquid crystal isstabilized to improve the transmittance in the region where thetransmission-side electrode 71 is formed and the region in the vicinityof the transmission-side electrode 71 can be obtained.

[Liquid Crystal Touch Panel of First Modification Example of SecondEmbodiment]

FIG. 21 illustrates a schematic structure of a cross-sectional surfaceof the liquid crystal touch panel 2 of the liquid crystal display deviceequipped with the touch sensor which is the display device of the firstmodification example of the second embodiment. Note that the liquidcrystal touch panel 2 of the first modification example of the secondembodiment is particularly referred to as a liquid crystal touch panel2B here. As similar to the second embodiment, while the liquid crystaltouch panel 2B of the first modification example of the secondembodiment includes the transmission-side electrode 71 and thereception-side electrode 72 configuring the touch panel function or thetouch sensor function, the transmission-side electrode 71 on one hand isprovided on the array substrate 10 side, and the reception-sideelectrode 72 is provided on the facing substrate 20 side. And, in theliquid crystal touch panel 2B of the first modification example of thesecond embodiment, the lower electrode 32 serving as the commonelectrode COM on the array substrate 10 side and the reception-sideelectrode 72 on the facing substrate 20 side have the same potential aseach other. That is, in the liquid crystal touch panel 2B of the firstmodification example of the second embodiment, the reception-sideelectrode 72 is provided as the conductive layer similar to theconductive layer 60 (see FIG. 2) in the liquid crystal panel 1A of thefirst embodiment.

In the array substrate 10, a position in the Z direction where thetransmission-side electrode 71 is provided is any position. That is, thetransmission-side electrode 71 on the array substrate 10 side can beprovided at any position in the Z direction. In the first modificationexample of the second embodiment, the lower electrode 32 serving as thecommon electrode COM and the transmission-side electrode 71 in theelectrode layer including the upper electrode 31 and the lower electrode32 of the array substrate 10 are commonly used and are functionallyshared. And, in the liquid crystal touch panel 2B of the firstmodification example of the second embodiment, the reception-sideelectrode 72 and the lower electrode 32 serving as the common electrodeCOM and the transmission-side electrode 71 have the same potential aseach other in a predetermined period.

In the facing substrate 20, a position in the Z direction where thereception-side electrode 72 is provided is any position. That is, thereception-side electrode 72 on the facing substrate 20 side can beprovided at any position in the Z direction. In the first modificationexample of the second embodiment, the layer of the reception-sideelectrode 72 is provided on the front surface side of the facingsubstrate 20, that is, on an outer surface side on the glass substrate21. As another aspect of the first modification example of the secondembodiment, the layer of the reception-side electrode 72 may be providedon an inner surface side of the glass substrate 21 included in thefacing substrate 20.

Also, as still another aspect of the first modification example of thesecond embodiment, the transmission-side electrode 71 may be provided onthe facing substrate 20 side, and the reception-side electrode 72 may beprovided on the array substrate 10 side. In this case, the lowerelectrode 32 and the transmission-side electrode 71 of the facingsubstrate 20 have the same potential as each other.

The lower electrode 32 serving as the common electrode COM provided onthe array substrate 10 side has a structure in which at least a part ofthe lower electrode 32 is commonly used with the transmission-sideelectrode 71 so that they can be driven and controlled by a commonvoltage. For example, the lower electrode 32 serving as the commonelectrode COM is commonly used with the transmission-side electrode 71by forming the lower electrode 32 as a solid layer as described in thesecond structure example of the touch sensor illustrated in FIG. 19. Inother words, in one layer of the lower electrode 32, a function servingas the common electrode COM and a function serving as thetransmission-side electrode 71 are commonly used. And, from the driverside, the signal, that is, the voltage for controlling the lowerelectrode 32 is supplied to the commonly-used layer when the liquidcrystal display function is used, and the touch drive signal is suppliedto the commonly-used layer when the touch sensor function is used. As afirst modification example of the second embodiment, note that the firststructure example of the touch sensor illustrated in FIG. 18 can be alsoused.

By the liquid crystal touch panel 2B of the first modification exampleof the second embodiment, as similar to the second embodiment, theorientation of the liquid crystal is stabilized in the space between thelower electrode 32 and the reception-side electrode 72 when the liquidcrystal display function is used, so that such an effect that thetransmittance is improved by the orientation stability of the liquidcrystal in the regions including the region in the vicinity of thereception-side electrode 72 in the X-Y planar view is obtained. In otherwords, in the X-Y planar view, the orientation of the liquid crystal isstabilized in the region where the reception-side electrode 72 is formedand the region in the vicinity of the reception-side electrode 72, sothat such an effect that the transmittance is improved is obtained.

[Manufacturing Method]

A method of manufacturing the liquid crystal touch panel 2 in the secondembodiment can be similar to the method of manufacturing the liquidcrystal panel 1 described in the first embodiment except for a pointthat the transmission-side electrode 71 and the reception-side electrode72 are formed.

[Mounting Structure Example]

A mounting structure example of the display device including the liquidcrystal touch panel 2 having the transmission-side electrode and thereception-side electrode of the second embodiment and the firstmodification example of the second embodiment can be similar to eitherof the first and second mounting structure examples described by usingFIGS. 6 and 7 in the first embodiment.

The mounting structure example similar to the first mounting structureexample described by using FIG. 6 corresponds to a case in which thereception-side electrode 72 serving as the conductive layer similar tothe conductive layer 60 is provided on the outer surface side of thefacing substrate 20 in the first modification example of the secondembodiment. In the mounting structure example similar to the firstmounting structure example, one end of the ITO pad 93 serving as thelower electrode 32 on the glass substrate 11 on the array substrate 10side and one end of the ITO 91 serving as the conductive layer, that is,the reception-side electrode 72 on the glass substrate 21 on the facingsubstrate 20 side are connected to each other by the conductive paste 92in an end region of the liquid crystal touch panel in the X or Ydirection.

On the other hand, the mounting structure example similar to the secondmounting structure example described by using FIG. 7 corresponds to acase in which the transmission-side electrode 71 serving as theconductive layer similar to the conductive layer 60 is provided on theinner surface side of the facing substrate 20 in the second embodiment.In the mounting structure example similar to the second mountingstructure example, one end of the lower electrode 32 and one end of theconductive layer, that is, the transmission-side electrode 71 areelectrically connected to each other by the conducting part 191 in theregion FA serving as the frame part of the liquid crystal touch panel.

[Structure Example of Upper Electrode and Lower Electrode]

A structure example regarding the upper electrode 31 and the lowerelectrode 32 which are applicable to the second embodiment and the firstmodification example of the second embodiment can be similar to any ofthe structure examples described by using FIGS. 8 to 10 in the firstembodiment.

[Planar Structure Example]

In the second embodiment and the first modification example of thesecond embodiment, a planar structure example of a pixel on an X-Y planecan be similar to any of the planar structure examples described byusing FIGS. 11A to 11D in the first embodiment.

[Drive Control Example]

While the second embodiment and the first modification example of thesecond embodiment have the liquid crystal display function and the touchpanel function, the liquid crystal display function and the touch panelfunction are controlled in, for example, time division as illustrated inthe following drive control example. The same voltage V0 is applied to,for example, the lower electrode 32 and the transmission-side electrode71 described above when the liquid crystal display function is used,that is, in the image display. When the touch panel function is used, apublicly-known touch detection process is performed.

FIG. 22 is a diagram illustrating an example of the drive control forthe liquid crystal touch panel 2 by the driver side in the liquidcrystal display device equipped with the touch sensor of the secondembodiment and the first modification example of the second embodiment.FIG. 22 illustrates timing of a drive waveform serving as the example ofthe drive control for the liquid crystal touch panel 2. FIG. 22illustrates the example of the drive control for supporting the driverstructure illustrated in FIG. 17. In the present example of the drivecontrol, a frame period is divided into a pixel write period and a touchdetection period, and the liquid crystal display function and the touchsensor function are driven in the time division. Items (a) to (g) ofFIG. 22 represent signals, that is, voltages, applied to the respectiveelectrodes. Note that a drive frequency in each period can beappropriately designed. For example, it is assumed that the drivefrequency in the pixel write period is set at 60 Hz and the drivefrequency in the touch detection period is set at 120 Hz which is doublethe drive frequency in the pixel write period. In this case, the touchdetection is performed in a ratio of twice with respect to the imagedisplay performed once. Also, an order of the pixel write period and thetouch detection period may be reversed. Further, a plurality of pixelwrite periods and touch detection periods may exist in the frame period.For example, one the pixel write period and one touch detection periodmay exist in one horizontal period of the frame period.

The item (a) of FIG. 22 represents an HSYNC signal for defining theframe period. The item (b) of FIG. 22 represents a scan signal from thegate driver 111 (see FIG. 17) to the gate line 41. The item (c) of FIG.22 represents a data signal from the data driver 112 (see FIG. 17) tothe data line 42. The item (d) of FIG. 22 represents a signal containinga pixel voltage V_(pix) to be applied from the upper/lower-electrodedriver 113 (see FIG. 17) to the upper electrode 31 serving as the pixelelectrode PIX in the case of the structure A. The item (e) of FIG. 22represents a signal containing a common voltage V_(com) to be appliedfrom the upper/lower-electrode driver 113 to the lower electrode 32serving as the common electrode COM in the case of the structure A. Theitem (f) of FIG. 22 represents a signal containing a voltage to beapplied from the touch panel electrode driver 114 (see FIG. 17) to thetransmission-side electrode 71. The item (g) of FIG. 22 represents avoltage to be applied from the touch panel electrode driver 114 to thereception-side electrode 72 and represents a signal to be outputted,that is, detected from the reception-side electrode 72 to the touchpanel electrode driver 114.

In the pixel write period, that is, in the image display by the liquidcrystal display function, as illustrated in the item (d) of FIG. 22, apredetermined pixel voltage V_(pix) (whose illustration is omitted) forcontrolling the orientation of the liquid crystal by causing the fringeelectric field in the liquid crystal layer 30 is applied to the upperelectrode 31 serving as the pixel electrode PIX in accordance with thepixel transmittance.

Also, as illustrated in the items (e) and (f) of FIG. 22, theabove-described same voltage V0 is applied as the common voltage V_(com)to the lower electrode 32 serving as the common electrode COM and thetransmission-side electrode 71 described above. In this manner, in thepixel write period, the lower electrode 32 and the transmission-sideelectrode 71 are controlled so as to have the same potential as eachother, so that the orientation stability of the liquid crystal isenhanced. Also to the reception-side electrode 72, the common voltageV_(com) is applied as similar to, for example, the lower electrode 32and the transmission-side electrode 71.

In the touch detection period, that is, in the touch detection by thetouch panel function, in the item (f) of FIG. 22, the input signal s1serving as a touch drive signal is inputted from the touch panelelectrode driver 114 to the transmission-side electrode 71. On the otherhand, in the item (g) of FIG. 22, the output signal s2 serving as atouch detection signal is outputted, that is, detected. In accordancewith the input signal s1 in the item (f) of FIG. 22, the same waveform,that is, potential as that of the input signal s1 is obtained also inthe items (d) and (e) of FIG. 22.

[Regarding Method of Driving Liquid Crystal]

In the liquid crystal touch panel 2 of any of the second embodiment andthe first modification example of the second embodiment, the opening 50including the plurality of slits S is formed in the electrode layerincluding the upper electrode 31 and the lower electrode 32 as describedin the first embodiment by using FIGS. 8 to 10 and 11A to 11D. Asdescribed in the first embodiment by using FIGS. 7 to 9 and 11A to 11D,the slits S extends in the transverse direction corresponding to thehorizontal direction of the screen, that is, in the X direction. Thehigh-speed transverse electric field mode which is the method of drivingthe liquid crystal for supporting the electrode layer and the opening 50is a method of achieving high-speed responsiveness and others by theorientation process for the anti-parallel orientation in accordance withthe X direction which is the extending direction of the slits S. Whilethis high-speed transverse electric field mode will be described later,and this is similar to the high-speed transverse electric field modedescribed in the first embodiment by using FIGS. 13 to 15.

In the second embodiment and the first modification example of thesecond embodiment, the liquid crystal touch panel 2 is configured byadding a touch panel function in addition to the liquid crystal displayfunction with the high-speed transverse electric field mode by theelectrode layer and the opening 50 described above. In such a case, atask for the orientation stability of the liquid crystal of the liquidcrystal layer is caused. That is, in order to achieve the favorableorientation stability of the liquid crystal of the liquid crystaldisplay function and others, there are tasks how to configure thetransmission-side electrode 71, the reception-side electrode 72, andothers for the liquid crystal panel and how to drive to control thetransmission-side electrode 71 and the reception-side electrode 72.

Accordingly, in the liquid crystal touch panel 2 of the secondembodiment and the first modification example of the second embodiment,the two types of layers also including the transmission-side electrode71 and the reception-side electrode 72 forming the touch panel function,such as the lower electrode 32 and the transmission-side electrode 71are controlled so as to have the same potential as each other. In thismanner, the orientation of the liquid crystal of the liquid crystallayer 30 can be stabilized. And, in addition to the achievement of thetouch panel function, the response speed or others in the pixel displaywhen the liquid crystal display function is used can be increased, sothat the display quality can be enhanced. In other words, thedegradation of the display quality and others caused by adding the touchpanel function formed of the transmission-side electrode 71 and thereception-side electrode 72 to the liquid crystal panel can be preventedor reduced.

[High-Speed Transverse Electric Field Mode]

The orientation state of the liquid crystal of the liquid crystal layer30 in the high-speed transverse electric field mode in the secondembodiment and the first modification example of the second embodimentis similar to the orientation state of the liquid crystal of the liquidcrystal layer 30 in the high-speed transverse electric field modedescribed in the first embodiment by using FIGS. 13 to 15. Therefore,also in the second embodiment and the first modification example of thesecond embodiment, as similar to the first embodiment, the pixelresponse speed obtained when the voltage is applied to the upperelectrode 31 and the lower electrode 32 is increased by this high-speedtransverse electric field mode, so that the display quality is enhanced.

[Effects and Others]

As described above, according to the liquid crystal display device ofeach embodiment, in addition to the wide viewing angle, the highaperture ratio, and others, it is possible to improve the responsespeed, the display quality, and others can be improved more than thoseof the conventional FFS mode or others. That is, according to the liquidcrystal display device of each embodiment, the liquid crystal displaydevice with the high-speed transverse electric field mode can beprovided. In other words, according to the liquid crystal display deviceof each embodiment, the orientation stability of the liquid crystal inthe pixel and on the screen can be improved, and the response speed,brightness, or others can be improved, so that the display quality canbe improved.

In the foregoing, the invention made by the present inventor has beenconcretely described based on the embodiments. However, it is needlessto say that the present invention is not limited to the foregoingembodiments and various modifications and alterations can be made withinthe scope of the present invention. For example, various modificationexamples as described below are possible for the shape of the opening 50formed of the upper electrode 31 and the lower electrode 32.

(1) The shapes of the slits S and the comb teeth can be various shapessuch as a rectangular, a trapezoidal, and a triangular shape. Forexample, the shape may be a triangular shape by setting a width of anupper side of the trapezoidal shape of each of the comb teeth K to be 0.

(2) In the structure α, the slits S on both sides in the X direction ofthe longitudinal-direction slit 57 extending in the Y direction may notbe arranged alternately in the Y direction of the longitudinal-directionslit 57 but may be arranged at the same position in the Y direction.That is, the comb teeth K on both sides of the longitudinal-directionelectrode part 58 extending in the Y direction may not be arrangedalternately in the Y direction of the longitudinal-direction slit 58 butmay be arranged at the same position in the Y direction. Also, thedegree of the shift in the case of the alternate shift arrangement isnot limited to ½ of the pitch of the slits S in the Y direction.Alternatively, not only each length of the slits S on both sides in theX direction of the longitudinal-direction slit 57 extending in the Ydirection but also each width and each pitch of the slits S in the Ydirection may be varied. That is, not only each length of the comb teethK on both sides in the X direction of the longitudinal-directionelectrode part 58 extending in the Y direction but also each width andeach pitch of the comb teeth K in the Y direction may be varied.

(3) The slits S of the opening 50 may be provided so that the extendingdirection of the slits S is tilted by a predetermined angle such as 5degrees from the X direction in the planar view. Also, two or more typesof the slits S whose extending directions are tilted by different anglesfrom each other from the X direction may be provided to be mixed insidethe pixel.

(4) Throughout the present specification, note that the pixel electrodePIX is taken as the upper electrode 31 and the common electrode COM istaken as the lower electrode 32. However, a vertically-structuredrelation between the pixel electrode PIX and the common electrode COM isnot limited to this. The common electrode COM may be formed on the pixelelectrode PIX via an insulating film.

(5) Further, the common electrode COM and the conductive layer 60 maynot necessarily have the same potential as each other. However, when thecommon electrode COM is formed on the pixel electrode PIX as describedin the item (4), it is more preferred that the common electrode COM andthe conductive layer 60 have different potentials from each other.

The present invention can be used for a liquid crystal display device orothers including a liquid crystal touch panel or others.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. A display device comprising: anelectrode layer being provided above a first substrate and including afirst electrode and a second electrode, the second electrode facing thefirst electrode and having an opening formed therein including aplurality of slits whose extending directions are the same as eachother; a liquid crystal layer being provided between the first substrateand a second substrate facing the first substrate and having liquidcrystal molecules oriented as rotating in reverse to each other invicinity regions on one side and the other side of the opening whichface each other in a width direction; and a conductive layer beingprovided above the second substrate, wherein the conductive layer isformed in a lattice form which sections pixels in accordance with pixelalignment when seen in a plan view, the display device further includes:a first orientation film being provided between the first substrate andthe liquid crystal layer and being subjected to an orientation processin a first orientation direction which is along an extending directionof the slits; and a second orientation film being provided between thesecond substrate and the liquid crystal layer and being subjected to anorientation process in a second orientation direction which is along afirst orientation direction of the first orientation film, in an initialorientation state of the liquid crystal layer, long axes of the liquidcrystal molecules are aligned in the first orientation direction, when ashort side direction of a pixel having a rectangle is set to a firstdirection, a long side direction of the pixel is set to a seconddirection, and a direction orthogonal to both of the first direction andthe second direction is set to a third direction, for each pixel, theopening includes: a communication opening extending in the seconddirection; a plurality of first slits each connected to one side of thecommunication opening in the first direction and each extending in thefirst direction; and a plurality of second slits each connected to theother side of the communication opening in the first direction and eachextending in the first direction, the first slits and the second slitsare alternately arranged so that their positions are shifted from eachother in the second direction, the second electrode includes a firstside extending in the first direction, a second side which extends inthe first direction and which is adjacent to the first side through thefirst slit, a third side extending in the first direction, and a fourthside which extends in the first direction and which is adjacent to thethird side through the second slit, each of the first side, the secondside, the third side, and the fourth side does not intersect thecommunication opening, and in application of the voltage to the firstelectrode and the second electrode, the long axes of the liquid crystalmolecules are oriented as rotating in an in-plane direction of asubstrate so that the liquid crystal molecules rotate clockwise in avicinity region including the first side of the first and second sidesof the first electrode forming each of the slits and the liquid crystalmolecules rotate counterclockwise in a vicinity region including thesecond side thereof.
 2. The display device according to claim 1,wherein, when orientation of liquid crystal of the liquid crystal layeris controlled, the conductive layer has the same potential as apotential of the first electrode or the second electrode.
 3. The displaydevice according to claim 1, wherein the first electrode is a commonelectrode, the second electrode is a pixel electrode arranged so as tobe closer to the liquid crystal layer than the first electrode, and theconductive layer has the same potential as a potential of the firstelectrode when orientation of liquid crystal of the liquid crystal layeris controlled.
 4. The display device according to claim 1, wherein thefirst electrode is a pixel electrode, the second electrode is a commonelectrode arranged so as to be closer to the liquid crystal layer thanthe first electrode, and the conductive layer has the same potential asa potential of the second electrode when orientation of liquid crystalof the liquid crystal layer is controlled.
 5. The display deviceaccording to claim 1, wherein the second substrate has atransmission-side electrode and a reception-side electrode which areelectrodes for configuring a touch sensor function as the conductivelayer, and the first electrode or the second electrode has the samepotential as a potential of the transmission-side electrode or thereception-side electrode when orientation of liquid crystal of theliquid crystal layer is controlled.
 6. The display device according toclaim 5, wherein the display device further includes: a first driverconnected to a first electrode line for configuring a pixel; a seconddriver connected to a second electrode line for configuring a pixel; athird driver connected to the second electrode and the first electrode;a fourth driver connected to the transmission-side electrode and thereception-side electrode; and a controller for controlling the first tofourth drivers.
 7. The display device according to claim 1, wherein thesecond substrate has one electrode of a transmission-side electrode anda reception-side electrode which are electrodes for configuring a touchsensor function as the conductive layer, the first substrate has theother electrode of the transmission-side electrode and thereception-side electrode, and the first electrode or the secondelectrode has the same potential as a potential of the one electrode ofthe transmission-side electrode and the reception-side electrode whenorientation of liquid crystal of the liquid crystal layer is controlled.8. The display device according to claim 1, wherein the conductive layeris an electrostatic protective layer.
 9. The display device according toclaim 1, wherein the display device further includes: a first drivecircuit part connected to the electrode layer; and a second drivecircuit part connected to the conductive layer, and, in a pixel writeperiod in image display, a first voltage is applied from the first drivecircuit part to either the second electrode or the first electrode, andbesides, the first voltage is applied from the second drive circuit partto the conductive layer.
 10. The display device according to claim 1,wherein the display device further includes a drive circuit partconnected to the first substrate or the second substrate, and a firstend of the first electrode or the second electrode extending to an endof the first substrate and a second end of the conductive layerextending to an end of the second substrate are connected to each otherby a conductive material, and a first voltage is applied from the drivecircuit part to the first end or the second end.
 11. The display deviceaccording to claim 1, wherein the display device further includes: adrive circuit part connected to the first substrate or the secondsubstrate; and a sealing part which connects between the first substrateand the second substrate and seals liquid crystal of the liquid crystallayer, and a first end of the first electrode or the second electrodeand a second end of the conductive layer are connected to each other bya conductive material at a position inside the sealing part itself orinner than the sealing part, and a first voltage is applied from thedrive circuit part to the first end or the second end.
 12. The displaydevice according to claim 1, wherein, one long side of each of the firstslits and one long side of each of the second slits are aligned on astraight line extending in the first direction.
 13. The display deviceaccording to claim 1, wherein the display device further includes: afirst driver connected to a first electrode line for configuring apixel; a second driver connected to a second electrode line forconfiguring a pixel; a third driver connected to the second electrodeand the first electrode; and a controller for controlling the first tothird drivers.
 14. An electronic apparatus comprising: the displaydevice according to claim 13; and a control unit for performing adisplay control process to the display device; and a storage unit forstoring display data to be provided to the display device.